3:04 12V Battery Build 8:10 Bluetooth Connection 10:39 Charging/ Low Temp Protection Test 11:52 Max Current Test 12:35 24V Battery Build 15:29 24V BMS Low Temp Charting Protection Test 16:16 24V BMS Continuous Current Test 17:25 Max Load Till OCP is Triggered 17:56 Conclusion This video was meant to be a review of the BMS, but I just realized that I built 2 full function batteries! I will show this video to beginners from now on. I hope this video helps you guys :D
Thank you for telling people about wearing safety glasses around the battery terminals. I normally always wear my safety goggles when doing any kind of work but it it's saved me the other day. I hooked up a inverter accidentally switching the polarity and the moment the terminal touch the stud all I could see was a blue flash of light and the only thing I could think was you talking about the story of solder hitting you in the eye.
I knew basically nothing about solar, making battery banks, or their related equipment before watching your videos. You are an excellent instructor and the way you take the time and effort to include every step in the process is incredibly helpful.
Just bought my Overkill BMS last night based on your previous recommendations. Then, I see this video today. So glad I went with quality equipment👍. Waiting for Overkill to come out with a 200-250A BMS 😉
I would love to see an in depth explanation video on how to use the Xiaoxiang BMS software and setup procedure to get best lifespan from lifepo4 battery.
Time for me to finally express some appreciation for your videos: really helpful. Building up my confidence to build a battery for our upcoming solar installation. Thank you so much for churning out these videos!
I’ve been running the 12v version for six months now and am extremely happy. Very easy to install and setup. Having the BT with app on my iphone makes it so simple to monitor. Had only one problem - the bulb on the temp sensor broke and he was VERY quick to send me a replacement. All in all a great product and great service. Heartily recommend.
I have a 48v byd lithium batteries but unfortunately i misplaceed a card in the Battery pack that commicates with the bms is it posible to use any other bms or is there a way to use the batteries without any issues??
Sorry, my last comment was absolutely wrong... newbie math. Parallel adds amps and volts remain same So my example cells are 3.2v 280ah In parallel is 3.2v560ah Four of these in series is 12.8 volts 560ah. Thanks Will, I've learned so much from you. Your a really good teacher.
At 7:20 you point to the main positive, but some people may not have noticed that you turned the battery around from the previous wiring up stage. Should be obvious since the main negative is now at the other end and covered, but sometimes it’s better to point out the obvious rather than let the “magic smoke” appear.
I was successful at connecting up my 300 amp ANT BMS with monitor without smoking the board and charged my 48 volt Leaf Powerwall using my PowMr Charge controller. I let the BMS stop the charge and it worked perfectly. I was able to figure out how to connect the leaf modules to the BMS and feel very confident moving forward. Next is to test the inverter with the setup before going to a huge battery bank for our off grid AC coupled setup. I have two sets of solar panels. One on the house which is 7.2 kW and one that will be ground mounted and 6kW. My home system does not seem to be putting out as much as when we first put it up. Im getting at best right now about 36 to 38kWh during the day if it is clear all day. I used to get 42kWh during the summer. Our system has been up and running since 2005. Im happy with the design of my power wall. A 6.6kWh pack if the cells are at 58 ah. I Have not done a capacity check yet. All cells are within .030 of each other. I did bottom balance all my cells/modules. I let the go until they were stable. Max charge to 8.1 volts.
I moved to these from Daly Smart BMS. Its so nice that it just works. One bug i noticed is that if you dont properly enter the parameters in the BT app, the BT can behave in a strange way.
Thank you from boomer notech artist i will not be making my own batpak yet but bcuz of your thorough study and teardowns thus recommendations ,I have learned enough to start with 2 100 watt panels and will choose a battgenerator for my bugout/camping /mobil massage/art studio trailer ... I am confident that you only promote the best ! I’m glad that you are getting compensation for your extensive work you have come so far ... I would love for you to write a book ( in your spare time ) about what you went through inspite of your difficulties ...what a no excuses life journey you stepped up and preavailed an inspiration to all young folks who feel lost and don’t think they have anything to contribute to the world bravo
Hey Will! I know this vid is 3 years old, but Id just like to thank you for all the great info on solar systems in general. This vid lead me to the Overkill BMS . I really didnt want to spend a fortune on Batrium or other BMS's that are like $1000! For all the features and performance, you really cant beat it. Im wiring up a 16s Eve 280AH pack to play with the BMS. If all goes well ill be getting another for my custom built 10Kwh cartridge style 18650 power wall. Ive been running it for 6 years with no BMS, just balancing it twice a year or so, but with the affordability and reliability of this BMS, im sure ill be getting a second one. The good thing about this vid being 3 years old is that Overkill is still in business so they can be trusted. Once again, Thanks!
Can't wait to get mine and get going on building my own with EVE 280 AH batteries. I just ordered it a few days ago along with your book Will. My cabin loses power often and this will come in handy. Batteries won't be here for another few weeks so I need patience.
I have this BMS for 8S! Overkill Solar was super cool to work with and he shipped and delivered within the week using USPS Priority. Upgraded to the 8ga 24” wire too - which is probably... overkill. It surged 4100w (170A) for my dryer as well. Even my 2000w gas generator failed at starting that motor. I’m glad I chose this BMS after watching your past videos. As much as I wanted a Chergery BMS it was just too much trouble when you factor in relays, etc. I trust the mosfets for my application and it’s barely more $ than a Daly BMS that doesn’t have all these cool features or reliability/quality control. Thanks Will!
@@rosskstar good timing on this post. I just happened to order another 8S BMS for a 304ah battery build. The site says the BMS is backordered but I ordered on a Saturday and it came to my door on a Wednesday! I’ve always wondered what other BMSs are out there but I’ve had such good luck with Overkill.
When you test a BMS it would be informative to measure the BMS input to output voltage drops as well as IR gun temp reading of case along with the discharge current used.
Couple of questions: 1) If one were to build a pair of 12v batteries out of the stereotypical-these-days 280Ah cells, each set with its own 12v 120a Overkill BMS; does the smartphone app keep the two BMSs straight? Can you switch between monitoring one or the other? 2) Your tests with the inverters had different limits due to the change in voltage and amp capacity of the BMS; but with the pair of 12v packs in the question above, each with its own BMS, would that double the watts the batteries could pump out, compared to if those same eight cells were configured into a 12v pack with a single 120a BMS? Thanks much! I appreciate how you don't mess around with your videos. Right to the good stuff.
Just built my first battery pack and after much deliberation between all of the BMS models out there, settled on the Overkill 4S 120A unit. What a great decision. Works perfectly, I can concur on the Bluetooth range, and just easy peasy to get everything up and running. The app just works. Can't be happier. They even will pre-install B- and C- leads to the BMS depending on your needs. And keeping true to the "Overkill" name, you can easily reduce the parameters as needed. So building a smaller pack is just as easy and you'll have a BMS that will allow you to increase the capacity of the pack later when you gain experience with handling this much energy.
So far so good for high quality. One wire missing on the connector, found another to replace the missing, connected BMS, one wire burned. Took apart BMS, a tin bridge shorting several contacts together, BMS sent cells into short - no surprise I saw the smoke. Test slip seems to be generated without connecting the actual BMS ... Communication with the seller ... well, it all sounded like I do not know what I was doing, huh.
I like this video. I bought your book in 2018 when I first discovered your channel. I just bought a cargo van and I am going to need a battery bank to run a induction stove and lights. You have been such a help in understanding the solar and battery world. Thanks
You will! It's pretty simple.. eventually. This man taught me and I've built my own system :) I also have a roomate who is smart on this stuff to fill in the gaps on things.
I have the 12V model now for about 2 months. Running IOS to control. I cant say enough about how easy this is to configure and use. NO problem at all connecting to IOS and it just works. Got it from WAMAZON for $115 and it has the absolute best ENGLISH manual. Steve makes sense when he says the first thing you do is parallel every cell and in a few days hook up the BMS. I wish the alarm would hit the IOS notification screen and it balances at something around 1 amp only so you have a challenge if you use B cells. I hang a few extra active cell balancers on my pack that I saw Will demo to make sure my solar system wont overpower just to be extra safe. It stops in and out as advertised when you go over or under what you set it to. And Steve if your watching this I am running a 4S 11P 100AH cell pack Grade B. Yes its giant for this little guy but I only push 400 watts in and run one large freezer out so I decided to not pay a zillion dollars for more sophistication.
I have a 12v and 24v Overkill Solar BMS that are about a year old now. One is on my trailer and the other is at my house. I love both of them, they work really well and are very reliable.
This is the exact system I bought. 24 v along with an MPPT controller. I'm having reservations turning it on. Don't know how to program MPPT control box. Don't have a DVD player to play disk. Will, you're the best.
Will I want to thank you for doing such a good job of explaining these new battery systems for us old school gearheads. I feel much more comfortable now that I have a better understanding of them. We are looking at an off-grid property that will need a solar system. Only we will need two systems one for the home and one for the shop and barn.
Thank you Will! I just built my Two 12v 320ah batteries, into Milwaukee Packout boxes, using OVERKILL solar BMSs.. I'm VERY happy with them both so far. Still testing Capacity, as I run my 12v Car freezer off them. However I'm very pleased with the batteries overall. My only complaint is that Overkill's app REQUIRES GPS location data be enabled, and seems to clog up my Android phone. Sometimes locking it up all together. However the reliability rating is worth the risk, considering I use a quality VPN (which might be the cause of the lockup). 🤣 I wish I could show you pictures, but... 🤨
I hate doing this here but love the videos no BS explanations. I am converting my liveaboard sailboat to lithium. Im new to lithium but fairly experienced in electronics from military experience years ago. Anyway I believe I'm going to go with your recommendations on the overkill batteries simply because of the ruggedness of the builds and what they will experience on a cruising sailboat. My issue comes in with the BMS. Most of the boat draws no more and typically far less than anything in your home with a maximum of 100 amps at short durations. AND then I have a Bow thruster that is also 12v it draws 400 amps (uses a 400 amp slow blow fuse so not full 400 typical) To be clear a Bow thruster is only used for 10 to 15 seconds over maybe 1 to 2 minutes so this isn't a space heater running all day heating up. Anyway the only bms I've found is this daly one that goes up to 500 amps but to be honest I'm not super excited about the quality the vibe the company puts off. They seem to be everywhere are a bright red and have a fan on the board. Is there some work around maybe better quality or are they trustworthy? I could parallel 2-200 amp BMS but then the build gets more complicated and I like simple when it comes to rugged. Maybe I'm missing something on the build and over complicating the thought process. Any advice from anyone is much appreciated.
Thank you for showing off quality materials and for demonstrating how to configure them. If I decide to go a DIY route, this gear will be the first on my list.
I'm glad I found your channel, I've done solar systems with with lead acid and old school tech. Now that we are looking at off grid property I see no reason not to setup using these newer battery system. Because my background is marine I plan to set-up the home with 12 or 24 volt for lighting and 48 volt for the inverter for AC power. When it comes to the shop it is going to be a different story because of the high amp draw of some the tools and welder.
Will, I have built 2 - 4S batteries using Docan 280 AH cells and 2 12V Overkill BMS. The BMS is active but when I connect the C- from the BMS to the chassis of the RV the BMS cuts off the current. I really appreciate your videos and have helped this rook immensely!.
I bought an 8S Overkill BMS back around July of 2020 and the app now looks better. Back when I downloaded it - it is a bit clunky and some nuisance bugs, but it looks like they have done some updates. Time to update my app, I guess. The BMS itself has worked flawlessly for me.
Will, you do excellent videos. This tutorial exactly matches up with what I'm doing for my truck. Setting up a 560 ah Eve system to run off-grid air conditioner when I'm parked at Truck Stops. I've watched most of your videos. So informative. Thank you
Yes! I’ve been waiting for this video!! I’m building a 48v battery bank with LiFePO4 cells for our electric sailboat and I’m looking at using this BMS 👍
Still back ordered and taking a month to fulfill orders. I ordered mine right after this video landed. I finally received word that due to Will reviewing this BMS, their sales quadrupled, and the BMS are finally in. They just need to be soldered then they can ship. Hoping next week!! I just got my cells from China, and cant wait to hook everything up!!
I bought a 12v and a 24v on your recommendation. I have used the 12v and it works perfectly with my 280ah 12v 4s, 2p. I have 2, 3kw inverters (12 & 24v) but I don't push too much amperage. IF I need more amperage for the 12v, I could probably buy another 12v 120a bms and run two packs into a multi battery switch.
That’s exactly what I want to do, there’s a guy on wills website that has just done that. One of wills other videos he bypasses the BMS with the inverter and uses a solid state relay in series to turn the inverter on..threw the Bms , so the switch can still be activated with low voltage disconnect.
hey hearing that is great, since i've been wondering if i could use this for a 280ah battery. I'll only ever be drawing a max of maybe 50ah, so the Overkill 120ah BMS should do me well? Anything I should be wary of?
This is an awesome video Will. Definitely building my confidence to build one myself. I appreciate your honesty in you videos and your willingness to demystify this for the rest of us! Thank you!
I love mine, they run my ac in the rv no problem, You could even stack them if you want to pull some really high amps but turning off charging on one. We need to support this guy and stop trying to save a couple off dollars on aliexpress, the owner is a boon to our realm.
Hi I like to say your the smartest person I ever seen on these systems, hope you know the average person can’t do this ,they have no training are knowledge to do this safe, I do love listening to you a man that knows it all , AAAAPlus Sir
Love your channel Will. I’m wanting to build a similar battery, but flattened out, not stacked together. Essentially a slimline battery pack. Keen to see you build one like that for low profile applications, like under a sub floor of a camper canopy
Just got mine and the new app with the xiaoxang is pure sickness. Huge upgrade over the older models(last year if you call that old) using this on android and no baloney getting the phone to take a .apk file like old models. Also glad the speed thing is gone i think these were made for ebikes previously. also if you are familiar with these alot of features that were locked with Chinese writing are now unlocked to English. I would rather have this setup then any off the shelf drop in lithium. The cold weather protection is PRICELESS and should be standard on all lithium batteries. The features on this new bluetooth BMS are unreal THANKS OVERKILL AND WILL another homerun product!
I just ordered a 12V BMS from overkill. Time to begin re-education for a modern lithium battery bank. I have several 315 watt pv panels. Too many panels, not enough batteries. I'll look into a 24 volt system later.
I was waiting for you to review an overkill! You said it was your favorite BMS but no review. Thanks for finally doing that review! Thumbs up and subscribed!
Hi Will, enjoying all your videos. Extremely educational and helpful. I am not surprised to see the view count. Most people are talking about the challenges around connecting a DIY BMS to an AC inverter using RS485 e.g. GroWatt AC3000. I don't see any useful info when I google. See if you can do a video please. Thanks.
I've read the entire manual, and while it implies OC protection can be set as high as 150A, I'm curious if you or anyone has tested this in practice. I'm pairing with a 6.5kW inverter, but don't expect to see more than 4-5kW continuous. Just curious how this BMS will handle inductive loads of ~7-8kW for a few hundred milliseconds. Thanks!
Awesome stuff Will 👍 I plan to build 4 of the 100ah/24v configuration soon. I've been building off grid systems for 11 years now, and this will be the first ever lithium based system! 😎 I was ready to make the switch a year ago, (based on your info then) and I came back to see what your current favorites were. Thanks.
In the Last Vid I watched you said not to connect the inverter last as its dangerous, in this vid you did exactly that XD Just an observation, keep up the great vids !
I just ordered this for my Ampere Time 200ah battery so that I can have low temp protection as well as more control. Taking the battery apart was a PITA but I think it will be worth it!
Darn! I wish you had made this a couple weeks earlier! I just bought an 8S and installed it on an old Enphase AC battery that had a dead comms board. I would have loved to use your links.
A sodium battery could be used in front of any condo parking spot charged all night and day slowly, then a higher discharge charger cold be used for a good five to eight hours of good vehicle charging. All this could be done easily for a condo renter or owner to have a power company to install a power connector from the living unit being charged for a little power used at low peak times.
Great channel, I watch almost everything you put out. I tried to order some of these Fortune cells from overkill solar but unless I order 64+ I can’t because I live in the UK, some rule. Keep up the good work.
Hi Will, I am a kayak guy and just came across your vids on building power banks. Awesome vids, I am Learning alot from them. So, I am looking to build 12V power systems for our kayak motors. Motors range from 30lb thrust to 55lb thrust. Power banks need to be no less than 12V 80AH. So I have a few questions, 1) What cells would you recommend. 2) Which BMS unit would you recommend. 3) Best charger for the power banks. The price of lithium batteries are very high and building my own seems like the best alternative. Thanks
Can you talk a little bit about your pre-charge resistor you use? Wattage/Ohms....sort of the specs you look for and why. Or maybe a link to Amazon to purchase one. Thanks! Your channel has helped me alot!
How do you configure the settings when running in parallel? I'll have some of the Lishen 272ah modules, so thinking two in parallel would be smart to support inductive/motor loads. Thanks!!!
@@Leander311 i have not touched the settings, just connected the bms’s to run parallel. I monitor the packs via the app, one at the tíme. A victron shunt is monitoring charge-discharge
That's my BMS of choice; not as sketchy as the Daly stuff. Odd you should post this right now when I'm getting ready to build something similar. The difference is I need 200 amps discharge at 12 volts nominal, so I am ordering 8 cells and 2 BMS (to avoid the sketchy ones). That will give me the output I need with 2 completely separate packs in one physical frame, paralleled after the BMS boards. At least that's my plan, subject to change thrice daily. LOL
@@msach4277 ..NAH.. I have a Truck/Camper. I CURRENT-ly ( LOL ) have 1 - 295w solar panel going into a 60 amp MPPT controller, 1- 275 w solar panel going into a 30amp MPPT controller, and 2- 100w solar panels that go into a 30 MPPT controller, or my Jackery 500 Explorer. ^ All the above controllers feed into 3-200Ah AGM Batteries for the Camper. I d love to replace the AGM's with 300-400Ah of Lithium Batteries.
@@RimdarRanch LOL!, that is quite a stash! You have way more than I do, and apparently a lot more space with the batteries you have.. My space is incredibly limited. Just bought Eve 12v, 280 amp lith batter(ies) off Alibaba, via recommended contact I found on DIYSolar. Price was not bad. Happy Camping!
You are the guy for me! I recently purchased a 200AH Lifepo4 battery on Amazon.... Not knowing I ran a little over 100A load for about 30 min and burned out the BMS inside, I took it apart and verified that. Its a 4S unit 100A. I am considering buying this bluetooth 4s100A BMS you show here ... All my cells are fine and I only had the battery for about a week so the cells have very low cycles. Would you agree that would be the thing to do and salvage this battery? The company sent me a replacement and told me to keep the old one so I figured why not fix it and use it in parallel with the new one giving 400AH 12V bank for my RV. When I took it apart I noticed the temp sensor was stuck in foam up against the plastic case and not on the cells themselves... poor design that it could dislodge like that. I am new at Lithium Ion and just wanted to make sure I am not missing anything? Is that what you would do?
Nice video. Looks like these BMSs are just a rebrand of the "LithiumBatteryPCB"/LLT Power Bluetooth BMSs, but I suppose with an extra QC and perhaps further calibration step done by Overkill. Not sure if it's worth the significant markup for the same BMS directly from the Manufacturer, but its a nice option to have. I've purchased a handful of Bluetooth BMSs from LLT directly and always had good results.
Hey Will, what are the dementions on those cells They look like they will fit my big 3 wheel scooter, it needs the batteries replaced. The cells that are on it right now, are 13 years old and have almost 60,000 miles on them, pretty good considering that I have never had a BMS installed, there was no BMS available that I could find at that time, so I have just manually balanced them, which was pretty easy when they were new, but not so much anymore. But I like that Over kill BMS and those cells are the first one's I have seen that look like they will fit. And you didn't mention the brand name of the cell's. Thank you in advance for your response. 😊 Nevermind I should have checked your link's below, but I got the info and yes these are just slightly smaller than my original cells, and 22 lbs lighter, but still the same ah's, and a 2C discharge rate, my old ones are only 1C. But the 6C intermittent for 10 seconds is double what my controller current limits at, it's amazing how much of an improvement there's been in next generation cells, not to mention I payed nearly $4,000 for my old ones and these I can get for just under $2,000. Awesome 👍😎👍
Looks like the 12V version is exactly what I need for my van box build, but they're on backorder with an alert that they're at least 30 days out... Gonna have to show up to the party earlier I guess!
Very nice device for lithium batteries BUT, we have only few options to regulate charging on gel or some other batteries. I have eight gel batteries 180ah, i got them used and they were connected in series so after few years they lost their balance. I think they can last much longer if they have controlled charging for each battery. If they are connected parallel, 3-4 in line, its much better because they are keeping balance together. But in series they are lost, and then they make problems.
10:17 _”If you cycle this a 1000 times, it will let you know”_ Is this information stored on the BMS or your phone? If it is stored on the BMS: Should you want to move this BMS to another pack, can these values be reset?
@@WillProwse When I upgraded my overkill software yesterday it deleted my cycles number so I assume it is stored on the phone. I didn't upgrade the firmware.
3:04 12V Battery Build
8:10 Bluetooth Connection
10:39 Charging/ Low Temp Protection Test
11:52 Max Current Test
12:35 24V Battery Build
15:29 24V BMS Low Temp Charting Protection Test
16:16 24V BMS Continuous Current Test
17:25 Max Load Till OCP is Triggered
17:56 Conclusion
This video was meant to be a review of the BMS, but I just realized that I built 2 full function batteries! I will show this video to beginners from now on. I hope this video helps you guys :D
It's perfect, i keep going back and forth between 12 and 24 volt but i think this sold me on a 8 cell 24 volt.
@@__WJK__ over an hour. The the pack was full
Forgive me if I missed it... how many minutes did the 12v configuration power the 126a/1610w load(?)
So with one of these, is there a point to running a shunt? Or is this accurate enough to replace needing a victron smart shunt?
Thanks so much both for the bms review and the updated 24v (and 12v) battery build. Fantastic!
Love the way you demonstrate each step. You’re an awesome teacher Will.
Thank you for telling people about wearing safety glasses around the battery terminals. I normally always wear my safety goggles when doing any kind of work but it it's saved me the other day. I hooked up a inverter accidentally switching the polarity and the moment the terminal touch the stud all I could see was a blue flash of light and the only thing I could think was you talking about the story of solder hitting you in the eye.
I knew basically nothing about solar, making battery banks, or their related equipment before watching your videos. You are an excellent instructor and the way you take the time and effort to include every step in the process is incredibly helpful.
Just bought my Overkill BMS last night based on your previous recommendations. Then, I see this video today. So glad I went with quality equipment👍. Waiting for Overkill to come out with a 200-250A BMS 😉
I would love to see an in depth explanation video on how to use the Xiaoxiang BMS software and setup procedure to get best lifespan from lifepo4 battery.
I thought that was different for each battery/pack?
@@cdoublejj parameters are set on the cell level and then extrapolated for the whole pack.
Time for me to finally express some appreciation for your videos: really helpful. Building up my confidence to build a battery for our upcoming solar installation. Thank you so much for churning out these videos!
Thanks 😁👍it can be scary at first, but it is super simple and fun after your first build. I'm glad I can help
Will you've taught me a lot on building as a Kenyan i appreciate your teaching skills .im really looking forward to building my first battery Thankyou
I’ve been running the 12v version for six months now and am extremely happy. Very easy to install and setup. Having the BT with app on my iphone makes it so simple to monitor. Had only one problem - the bulb on the temp sensor broke and he was VERY quick to send me a replacement. All in all a great product and great service. Heartily recommend.
Do you know if it also works with Android?
Got the link to the app from Overkill’s website. I haven’t checked but I’s be extremely surprised if there was not one for android.
@@scothunter3221 I just looked at the Overkill page from Wills link. It says programmable with Android. Thanks. !:- )
I have a 48v byd lithium batteries but unfortunately i misplaceed a card in the Battery pack that commicates with the bms is it posible to use any other bms or is there a way to use the batteries without any issues??
Sorry, my last comment was absolutely wrong... newbie math.
Parallel adds amps and volts remain same
So my example cells are 3.2v 280ah
In parallel is 3.2v560ah
Four of these in series is 12.8 volts 560ah.
Thanks Will, I've learned so much from you. Your a really good teacher.
At 7:20 you point to the main positive, but some people may not have noticed that you turned the battery around from the previous wiring up stage. Should be obvious since the main negative is now at the other end and covered, but sometimes it’s better to point out the obvious rather than let the “magic smoke” appear.
I was successful at connecting up my 300 amp ANT BMS with monitor without smoking the board and charged my 48 volt Leaf Powerwall using my PowMr Charge controller. I let the BMS stop the charge and it worked perfectly. I was able to figure out how to connect the leaf modules to the BMS and feel very confident moving forward. Next is to test the inverter with the setup before going to a huge battery bank for our off grid AC coupled setup. I have two sets of solar panels. One on the house which is 7.2 kW and one that will be ground mounted and 6kW. My home system does not seem to be putting out as much as when we first put it up. Im getting at best right now about 36 to 38kWh during the day if it is clear all day. I used to get 42kWh during the summer. Our system has been up and running since 2005. Im happy with the design of my power wall. A 6.6kWh pack if the cells are at 58 ah. I Have not done a capacity check yet. All cells are within .030 of each other. I did bottom balance all my cells/modules. I let the go until they were stable. Max charge to 8.1 volts.
I moved to these from Daly Smart BMS. Its so nice that it just works. One bug i noticed is that if you dont properly enter the parameters in the BT app, the BT can behave in a strange way.
Do a video on this BMS in parallel next!
Thank you from boomer notech artist i will not be making my own batpak yet but bcuz of your thorough study and teardowns thus recommendations ,I have learned enough to start with 2 100 watt panels and will choose a battgenerator for my bugout/camping /mobil massage/art studio trailer ... I am confident that you only promote the best ! I’m glad that you are getting compensation for your extensive work you have come so far ... I would love for you to write a book ( in your spare time ) about what you went through inspite of your difficulties ...what a no excuses life journey you stepped up and preavailed an inspiration to all young folks who feel lost and don’t think they have anything to contribute to the world bravo
Hey Will! I know this vid is 3 years old, but Id just like to thank you for all the great info on solar systems in general. This vid lead me to the Overkill BMS . I really didnt want to spend a fortune on Batrium or other BMS's that are like $1000! For all the features and performance, you really cant beat it. Im wiring up a 16s Eve 280AH pack to play with the BMS. If all goes well ill be getting another for my custom built 10Kwh cartridge style 18650 power wall. Ive been running it for 6 years with no BMS, just balancing it twice a year or so, but with the affordability and reliability of this BMS, im sure ill be getting a second one. The good thing about this vid being 3 years old is that Overkill is still in business so they can be trusted. Once again, Thanks!
Can't wait to get mine and get going on building my own with EVE 280 AH batteries. I just ordered it a few days ago along with your book Will. My cabin loses power often and this will come in handy. Batteries won't be here for another few weeks so I need patience.
Where did you find these with such a short turnaround time?
@@Orangie2008 order the batteries 6 weeks ago from ali express knowing they would take time. I just ordered the bms a few days ago.
I have this BMS for 8S! Overkill Solar was super cool to work with and he shipped and delivered within the week using USPS Priority. Upgraded to the 8ga 24” wire too - which is probably... overkill.
It surged 4100w (170A) for my dryer as well. Even my 2000w gas generator failed at starting that motor. I’m glad I chose this BMS after watching your past videos. As much as I wanted a Chergery BMS it was just too much trouble when you factor in relays, etc. I trust the mosfets for my application and it’s barely more $ than a Daly BMS that doesn’t have all these cool features or reliability/quality control. Thanks Will!
They're way cheaper than REC BMS - does that mean REC is severely overpriced with all the add-ons one must buy? i wonder...
@@rosskstar good timing on this post. I just happened to order another 8S BMS for a 304ah battery build. The site says the BMS is backordered but I ordered on a Saturday and it came to my door on a Wednesday! I’ve always wondered what other BMSs are out there but I’ve had such good luck with Overkill.
When you test a BMS it would be informative to measure the BMS input to output voltage drops as well as IR gun temp reading of case along with the discharge current used.
Couple of questions:
1) If one were to build a pair of 12v batteries out of the stereotypical-these-days 280Ah cells, each set with its own 12v 120a Overkill BMS; does the smartphone app keep the two BMSs straight? Can you switch between monitoring one or the other?
2) Your tests with the inverters had different limits due to the change in voltage and amp capacity of the BMS; but with the pair of 12v packs in the question above, each with its own BMS, would that double the watts the batteries could pump out, compared to if those same eight cells were configured into a 12v pack with a single 120a BMS?
Thanks much! I appreciate how you don't mess around with your videos. Right to the good stuff.
Just built my first battery pack and after much deliberation between all of the BMS models out there, settled on the Overkill 4S 120A unit. What a great decision. Works perfectly, I can concur on the Bluetooth range, and just easy peasy to get everything up and running. The app just works. Can't be happier. They even will pre-install B- and C- leads to the BMS depending on your needs. And keeping true to the "Overkill" name, you can easily reduce the parameters as needed. So building a smaller pack is just as easy and you'll have a BMS that will allow you to increase the capacity of the pack later when you gain experience with handling this much energy.
So far so good for high quality. One wire missing on the connector, found another to replace the missing, connected BMS, one wire burned. Took apart BMS, a tin bridge shorting several contacts together, BMS sent cells into short - no surprise I saw the smoke. Test slip seems to be generated without connecting the actual BMS ... Communication with the seller ... well, it all sounded like I do not know what I was doing, huh.
I like this video. I bought your book in 2018 when I first discovered your channel. I just bought a cargo van and I am going to need a battery bank to run a induction stove and lights. You have been such a help in understanding the solar and battery world. Thanks
I like that the Bluetooth module is included!
I figure if I keep listening to you I will someday understand electricity.
You will! It's pretty simple.. eventually. This man taught me and I've built my own system :) I also have a roomate who is smart on this stuff to fill in the gaps on things.
I have the 12V model now for about 2 months. Running IOS to control. I cant say enough about how easy this is to configure and use. NO problem at all connecting to IOS and it just works. Got it from WAMAZON for $115 and it has the absolute best ENGLISH manual. Steve makes sense when he says the first thing you do is parallel every cell and in a few days hook up the BMS. I wish the alarm would hit the IOS notification screen and it balances at something around 1 amp only so you have a challenge if you use B cells. I hang a few extra active cell balancers on my pack that I saw Will demo to make sure my solar system wont overpower just to be extra safe. It stops in and out as advertised when you go over or under what you set it to.
And Steve if your watching this I am running a 4S 11P 100AH cell pack Grade B. Yes its giant for this little guy but I only push 400 watts in and run one large freezer out so I decided to not pay a zillion dollars for more sophistication.
Brutal. Super good video. Very nice BMS, I want one. The lid of these batteries gives a protective and attractive appearance.
I have a 12v and 24v Overkill Solar BMS that are about a year old now. One is on my trailer and the other is at my house. I love both of them, they work really well and are very reliable.
This is the exact system I bought. 24 v along with an MPPT controller. I'm having reservations turning it on. Don't know how to program MPPT control box. Don't have a DVD player to play disk. Will, you're the best.
I love at the start you mention it's a product you actually like with great surprise... Because there is some much trash out there 🤣 great video!
Hahahaha
Exactly
I wish more companies would focus on quality
I think I'd add numbering labels to the balance leads whilst making the cable. It saves errors and makes harness setup/maintenance really easy
I am a total beginner and used the overkill solar 8s 1p to create a 24v system...great product very happy planning to create 2 more
Will I want to thank you for doing such a good job of explaining these new battery systems for us old school gearheads. I feel much more comfortable now that I have a better understanding of them.
We are looking at an off-grid property that will need a solar system. Only we will need two systems one for the home and one for the shop and barn.
Thank you Will!
I just built my Two 12v 320ah batteries, into Milwaukee Packout boxes, using OVERKILL solar BMSs.. I'm VERY happy with them both so far. Still testing Capacity, as I run my 12v Car freezer off them. However I'm very pleased with the batteries overall.
My only complaint is that Overkill's app REQUIRES GPS location data be enabled, and seems to clog up my Android phone. Sometimes locking it up all together.
However the reliability rating is worth the risk, considering I use a quality VPN (which might be the cause of the lockup). 🤣
I wish I could show you pictures, but... 🤨
Perfect timing! I was just looking at buying a 24v BMS for my 280ah system
Also Canadian in BC just ordered 24v BMS for my 280Ah system!
I hate doing this here but love the videos no BS explanations. I am converting my liveaboard sailboat to lithium. Im new to lithium but fairly experienced in electronics from military experience years ago. Anyway I believe I'm going to go with your recommendations on the overkill batteries simply because of the ruggedness of the builds and what they will experience on a cruising sailboat.
My issue comes in with the BMS. Most of the boat draws no more and typically far less than anything in your home with a maximum of 100 amps at short durations. AND then I have a Bow thruster that is also 12v it draws 400 amps (uses a 400 amp slow blow fuse so not full 400 typical) To be clear a Bow thruster is only used for 10 to 15 seconds over maybe 1 to 2 minutes so this isn't a space heater running all day heating up. Anyway the only bms I've found is this daly one that goes up to 500 amps but to be honest I'm not super excited about the quality the vibe the company puts off. They seem to be everywhere are a bright red and have a fan on the board.
Is there some work around maybe better quality or are they trustworthy? I could parallel 2-200 amp BMS but then the build gets more complicated and I like simple when it comes to rugged.
Maybe I'm missing something on the build and over complicating the thought process.
Any advice from anyone is much appreciated.
Thank you for showing off quality materials and for demonstrating how to configure them. If I decide to go a DIY route, this gear will be the first on my list.
I'm glad I found your channel, I've done solar systems with with lead acid and old school tech.
Now that we are looking at off grid property I see no reason not to setup using these newer battery system.
Because my background is marine I plan to set-up the home with 12 or 24 volt for lighting and 48 volt for the inverter for AC power.
When it comes to the shop it is going to be a different story because of the high amp draw of some the tools and welder.
Thanks for testing these BMSes! 😁 I'm definitely sold now. I like how many configurable settings there are.
brilliant beautiful wonderful… Thank you from a resident of a former first world country above mexico below canada
Will, I have built 2 - 4S batteries using Docan 280 AH cells and 2 12V Overkill BMS. The BMS is active but when I connect the C- from the BMS to the chassis of the RV the BMS cuts off the current. I really appreciate your videos and have helped this rook immensely!.
I bought an 8S Overkill BMS back around July of 2020 and the app now looks better. Back when I downloaded it - it is a bit clunky and some nuisance bugs, but it looks like they have done some updates. Time to update my app, I guess. The BMS itself has worked flawlessly for me.
Your videos keep getting better! Great job!
I've bought several BMS' from Overkill over the last couple of years and never a problem. Good reference video, thanks!
Will, you do excellent videos. This tutorial exactly matches up with what I'm doing for my truck. Setting up a 560 ah Eve system to run off-grid air conditioner when I'm parked at Truck Stops. I've watched most of your videos. So informative. Thank you
Yes! I’ve been waiting for this video!!
I’m building a 48v battery bank with LiFePO4 cells for our electric sailboat and I’m looking at using this BMS 👍
Still back ordered and taking a month to fulfill orders. I ordered mine right after this video landed. I finally received word that due to Will reviewing this BMS, their sales quadrupled, and the BMS are finally in. They just need to be soldered then they can ship. Hoping next week!!
I just got my cells from China, and cant wait to hook everything up!!
I bought a 12v and a 24v on your recommendation. I have used the 12v and it works perfectly with my 280ah 12v 4s, 2p. I have 2, 3kw inverters (12 & 24v) but I don't push too much amperage. IF I need more amperage for the 12v, I could probably buy another 12v 120a bms and run two packs into a multi battery switch.
That’s exactly what I want to do, there’s a guy on wills website that has just done that. One of wills other videos he bypasses the BMS with the inverter and uses a solid state relay in series to turn the inverter on..threw the Bms , so the switch can still be activated with low voltage disconnect.
hey hearing that is great, since i've been wondering if i could use this for a 280ah battery. I'll only ever be drawing a max of maybe 50ah, so the Overkill 120ah BMS should do me well? Anything I should be wary of?
Wow that is a really clean set up I’d love to put that in my house boat
This is an awesome video Will. Definitely building my confidence to build one myself. I appreciate your honesty in you videos and your willingness to demystify this for the rest of us! Thank you!
I love mine, they run my ac in the rv no problem, You could even stack them if you want to pull some really high amps but turning off charging on one. We need to support this guy and stop trying to save a couple off dollars on aliexpress, the owner is a boon to our realm.
Hi I like to say your the smartest person I ever seen on these systems, hope you know the average person can’t do this ,they have no training are knowledge to do this safe, I do love listening to you a man that knows it all , AAAAPlus Sir
Love your channel Will.
I’m wanting to build a similar battery, but flattened out, not stacked together.
Essentially a slimline battery pack.
Keen to see you build one like that for low profile applications, like under a sub floor of a camper canopy
Just got mine and the new app with the xiaoxang is pure sickness. Huge upgrade over the older models(last year if you call that old) using this on android and no baloney getting the phone to take a .apk file like old models. Also glad the speed thing is gone i think these were made for ebikes previously. also if you are familiar with these alot of features that were locked with Chinese writing are now unlocked to English. I would rather have this setup then any off the shelf drop in lithium. The cold weather protection is PRICELESS and should be standard on all lithium batteries. The features on this new bluetooth BMS are unreal
THANKS OVERKILL AND WILL another homerun product!
I have the 4S 12V 120 model and have been very happy with it.
I love this guys videos!...I learn something every time I watch one...that pack he just put together would be great for a small electric car..
I just ordered a 12V BMS from overkill. Time to begin re-education for a modern lithium battery bank. I have several 315 watt pv panels. Too many panels, not enough batteries. I'll look into a 24 volt system later.
Great video Will Like the fact your using Safety glasses/ goggles In the trade we call them Spoggles They are
used usually on windy days on a
jobsite
I was waiting for you to review an overkill! You said it was your favorite BMS but no review. Thanks for finally doing that review! Thumbs up and subscribed!
Hi Will, enjoying all your videos. Extremely educational and helpful. I am not surprised to see the view count. Most people are talking about the challenges around connecting a DIY BMS to an AC inverter using RS485 e.g. GroWatt AC3000. I don't see any useful info when I google. See if you can do a video please. Thanks.
I have this BMS, it’s truly amazing, I just wish they would make a higher amp one.
I've read the entire manual, and while it implies OC protection can be set as high as 150A, I'm curious if you or anyone has tested this in practice. I'm pairing with a 6.5kW inverter, but don't expect to see more than 4-5kW continuous. Just curious how this BMS will handle inductive loads of ~7-8kW for a few hundred milliseconds. Thanks!
@@Leander311 I’m not going to risk it 🤔I’ve actually ordered another bms to run in parallel with the existing one.
@@toastiesvanbuild4644are you getting equal output?
does it need an equalizer or it's all in one?
Awesome stuff Will 👍
I plan to build 4 of the 100ah/24v configuration soon.
I've been building off grid systems for 11 years now, and this will be the first ever lithium based system! 😎
I was ready to make the switch a year ago, (based on your info then) and I came back to see what your current favorites were.
Thanks.
This looks really cool and very reliable products ! A nice overview, well done !
Perfect timing mate. I'm just about to update my 2x BMS out of my bank this looks perfect for my bank Thanks
Another GREAT video!
You Are without a doubt my go to source for solar!
In the Last Vid I watched you said not to connect the inverter last as its dangerous, in this vid you did exactly that XD Just an observation, keep up the great vids !
My Overkill has been flawless on my 130AH pack
I bought this one two weeks before you posted this video. I'm glad you approve my choice
I use the 12v version, worth every penny. Love this bms
I just ordered this for my Ampere Time 200ah battery so that I can have low temp protection as well as more control. Taking the battery apart was a PITA but I think it will be worth it!
I got nearly the same two today from Overkill!
Darn! I wish you had made this a couple weeks earlier! I just bought an 8S and installed it on an old Enphase AC battery that had a dead comms board. I would have loved to use your links.
A sodium battery could be used in front of any condo parking spot charged all night and day slowly, then a higher discharge charger cold be used for a good five to eight hours of good vehicle charging. All this could be done easily for a condo renter or owner to have a power company to install a power connector from the living unit being charged for a little power used at low peak times.
Thanks Will! Yet another very helpful video and review.
life saver this was the exact configuration i was about to do even bought the frotune cells
Thank you thank you! I’m now ready to pull the trigger and start my battery build :)
Great channel, I watch almost everything you put out. I tried to order some of these Fortune cells from overkill solar but unless I order 64+ I can’t because I live in the UK, some rule. Keep up the good work.
Thanks for another good test och video. Plan to buy two OverKilll 120A too a
440 (or 660) Ah pack, 2000W inverter.
Hi Will, I am a kayak guy and just came across your vids on building power banks. Awesome vids, I am Learning alot from them. So, I am looking to build 12V power systems for our kayak motors. Motors range from 30lb thrust to 55lb thrust. Power banks need to be no less than 12V 80AH. So I have a few questions, 1) What cells would you recommend. 2) Which BMS unit would you recommend. 3) Best charger for the power banks. The price of lithium batteries are very high and building my own seems like the best alternative. Thanks
i will absolutely be picking up one of these. thanks so much!
Would be cool to see an infrared camera shot. New toy time!
Can you talk a little bit about your pre-charge resistor you use? Wattage/Ohms....sort of the specs you look for and why. Or maybe a link to Amazon to purchase one. Thanks! Your channel has helped me alot!
Will uses any low ohm as in 4-20 ohm resistor you might have. Something that will charge the internal capacitor in the inverter quickly
I have 2 of the 12v bms.s for my 200A batteries. It just works 👍🏼 have taken out 240A as parallell no problem 👍🏼
How do you configure the settings when running in parallel? I'll have some of the Lishen 272ah modules, so thinking two in parallel would be smart to support inductive/motor loads. Thanks!!!
@@Leander311 i have not touched the settings, just connected the bms’s to run parallel. I monitor the packs via the app, one at the tíme. A victron shunt is monitoring charge-discharge
Thanks Will, I got one of these on the way, I cant wait!
That's my BMS of choice; not as sketchy as the Daly stuff. Odd you should post this right now when I'm getting ready to build something similar. The difference is I need 200 amps discharge at 12 volts nominal, so I am ordering 8 cells and 2 BMS (to avoid the sketchy ones). That will give me the output I need with 2 completely separate packs in one physical frame, paralleled after the BMS boards. At least that's my plan, subject to change thrice daily. LOL
Just picked up the 12v 4s, well worth money
When you get bored with that SWEET 12v battery pack you can send it to MEEEE ! Awesome video. I could use this in my Bug-out Camper.
Hey Gerald, if you are talking about a VW camper, that is what I am working on - solar wise - just beginning to learn...
@@msach4277 ..NAH.. I have a Truck/Camper. I CURRENT-ly ( LOL ) have 1 - 295w solar panel going into a 60 amp MPPT controller, 1- 275 w solar panel going into a 30amp MPPT controller, and 2- 100w solar panels that go into a 30 MPPT controller, or my Jackery 500 Explorer. ^ All the above controllers feed into 3-200Ah AGM Batteries for the Camper. I d love to replace the AGM's with 300-400Ah of Lithium Batteries.
@@RimdarRanch LOL!, that is quite a stash! You have way more than I do, and apparently a lot more space with the batteries you have.. My space is incredibly limited. Just bought Eve 12v, 280 amp lith batter(ies) off Alibaba, via recommended contact I found on DIYSolar. Price was not bad. Happy Camping!
Nice very easy! Already have my batteries set up but your video make me do again 😄😩
I love the return policy
You are the guy for me! I recently purchased a 200AH Lifepo4 battery on Amazon.... Not knowing I ran a little over 100A load for about 30 min and burned out the BMS inside, I took it apart and verified that. Its a 4S unit 100A. I am considering buying this bluetooth 4s100A BMS you show here ... All my cells are fine and I only had the battery for about a week so the cells have very low cycles. Would you agree that would be the thing to do and salvage this battery? The company sent me a replacement and told me to keep the old one so I figured why not fix it and use it in parallel with the new one giving 400AH 12V bank for my RV. When I took it apart I noticed the temp sensor was stuck in foam up against the plastic case and not on the cells themselves... poor design that it could dislodge like that. I am new at Lithium Ion and just wanted to make sure I am not missing anything? Is that what you would do?
Nice video. Looks like these BMSs are just a rebrand of the "LithiumBatteryPCB"/LLT Power Bluetooth BMSs, but I suppose with an extra QC and perhaps further calibration step done by Overkill. Not sure if it's worth the significant markup for the same BMS directly from the Manufacturer, but its a nice option to have. I've purchased a handful of Bluetooth BMSs from LLT directly and always had good results.
I need to look up these cells. Ha omg done a BMS upgrade.this pack seems damn simple. The case would be the most complex part.
appreciate the safety reminder .. often taken too lightly
Yes. I was fussing with things yesterday and stopped and got glasses. “Will says wear glasses. I better go get my glasses”.
Great review and I'll be heading over to Over Kill Solar
Hey Will, what are the dementions on those cells
They look like they will fit my big 3 wheel scooter, it needs the batteries replaced. The cells that are on it right now, are 13 years old and have almost 60,000 miles on them, pretty good considering that I have never had a BMS installed, there was no BMS available that I could find at that time, so I have just manually balanced them, which was pretty easy when they were new, but not so much anymore. But I like that Over kill BMS and those cells are the first one's I have seen that look like they will fit. And you didn't mention the brand name of the cell's. Thank you in advance for your response. 😊 Nevermind I should have checked your link's below, but I got the info and yes these are just slightly smaller than my original cells, and 22 lbs lighter, but still the same ah's, and a 2C discharge rate, my old ones are only 1C. But the 6C intermittent for 10 seconds is double what my controller current limits at, it's amazing how much of an improvement there's been in next generation cells, not to mention I payed nearly $4,000 for my old ones and these I can get for just under $2,000. Awesome 👍😎👍
Looks like the 12V version is exactly what I need for my van box build, but they're on backorder with an alert that they're at least 30 days out... Gonna have to show up to the party earlier I guess!
Very nice device for lithium batteries BUT, we have only few options to regulate charging on gel or some other batteries.
I have eight gel batteries 180ah, i got them used and they were connected in series so after few years they lost their balance. I think they can last much longer if they have controlled charging for each battery.
If they are connected parallel, 3-4 in line, its much better because they are keeping balance together. But in series they are lost, and then they make problems.
This is a fantastic video. The BMS looks like it made the grade. !:- )
10:17 _”If you cycle this a 1000 times, it will let you know”_
Is this information stored on the BMS or your phone?
If it is stored on the BMS: Should you want to move this BMS to another pack, can these values be reset?
It is stored in bms, and yes you can reset the cycle counter.
@@WillProwse When I upgraded my overkill software yesterday it deleted my cycles number so I assume it is stored on the phone. I didn't upgrade the firmware.
@@WillProwse how high will it count to
How do you reset the cycle counter ?
An interesting and appreciated effort, thank you