David...this is an awesome project, but u definitely know what u r doing in regards to DC currents and voltages etc and the use of meters, heating etc, what is your background, are u a technician...thks..i would love to try that set up but not understanding the principles of DC electricity, one could harm himself..thks
Can I buy that battery from you? I have a back injury at the moment and can't get around to do much. I am living on my sailboat in Seabrook Texas and need a decent power supply. I would appreciate it. If you aren't using it that is?
It cost him $ 440, less his labour, a battery that spec, worth 900 to 1100 k, so ill assume he means, he saved 500, if he sells them for 900,he made 500,for that day project, but he should say this , tp not look click baitish
Awesome thing to build your own battery David! Amazing what you have learned about all this stuff because you were not afraid to try. Your kids are also watching and learning. They'll be awesome as well. You and your wife are great parents.
SON! probably the best presentation of any subject I have watched on u'tube! I've been to automotive and aircraft schools off and on over the 55 years in the mechanical field. I had only a couple of instructors that presented the info as concise as your did, and that's including speech delivery, clear! Thanks!
Thank you David for sharing your build video. I found it interesting and was impressed with your attention to detail. I hope your battery serves you well for a long time to come.
Impressive build. Very well done. Loved the logo. I felt as if I were actually building this along with you. Very detailed and you explained the process well. Bravo!
I'm sure you already know this but cells with built in battery protection circuits tend to be longer, even though they can be marked as 18650. Some of these circuits can add 5mm to the length and this may be why. If you rip the plastic wrapper off one, you might find one tacked onto the end of a cell.
For me it does not look professional due to some severe points missing: - How to protect against short circuiting when attaching the bms - Design flaws: the "prepared" end nickel construction has only the 8mm strips to combine the two left and right sided cell strings and those can easily provide 20 amps each, but you told us the strip is good for 5 amps. That is a severe heating source! - Not repair-friendly: welding 20 cells makes them very hard to find broken ones and to replace them - The welding points can heat up - More information about the welding hardware would be desirable - and lots more
Knowledge is priceless! I've learned so many practical stuff in this video alone that you can extend to so many other projects. Kudos to you, David. Love the the logo too ;-)
knowledge may be priceless but think of something someone learned after 5 yrs of experience and showing you when you just started to learn about it thats huge thank you for sharing tricks.
I disagree. I say this after spending ~$1000 in nissan leaf modules/lg battereis/harnesses/BMS's and all the messed up wire crimping/messed up power supplies. Even after spending hours watching these youtube videos, you still have to DO IT. That's where the rubber meets the road and you end up creating knowledge. For instance, bms's are designed to keep a cell from getting damaged...if you connect several batteries in parallel and then hook them up to a BMS, you can still damage batteries because the bms treats the group as 1 and can't tell if any 1 of them has gone below/above the set voltages, so if 1 of them goes beyond those bounds, the others will make up the difference on the top/bottom which will eventually ruin the whole group.
Well done I use to install solar systems in the 80s we used lead acid fork lift battery's. The battery banks were usually only 48 volt systems so there was not a hazard from getting shocked but a short across a battery battery bank will do severe damage to anything near by. Take every precaution to not let the positive and negative leads touch the amperage is very height and will weld and or vaporize conductors.
wow man i have never seen such a detailed build, most people will stop after the spot welding, but that final parts cost sheet is the icing on the cake.
@@InnovativeSustainableSolutions if u copy him it shouldnt take u any longer than that, its not that complicated or a time consuming task, unless u are not familiar with all the basics of what he did to begin with, then it may take u some time. If u are someone like me that is always messing with these types of things then it should actually take less time, its all about proper prep. Proper prep is one of the most important steps, and ultimately what saves u time. I usually write up steps and everything i need on white board, and layout everything according to my steps.This guy did all the layout and figuring out everything to do. Ur part is basically just assembly, The way I approach things is get everything together tools materals and lay them out in as needed order where possible, battery case on end, say 30 or so minutes getting everything rdy lay out ur cells and put them together that isnt a long process cut materials to length spot weld on etc.. Its easy to see what took him so long, there are a lot of extra problems to solve along with how to do the battery for video. I find most people over think most things and make it harder for themselves.
Great video! Nice to see someone who really knows their topic well, that can explain it, & with measurements taken all along the way. Even detail on spot welder temperature is above & beyond call of duty! Thanks
I think it's awesome what you did Sir keep up the good work I'll be following you. I'm in the beginning process of a shuttle bus conversion looking into lithium batteries.
Thank you for the great video which I came across accidentally. I am sure I learned something new, you explained very well and with great camera work. you are a good teacher.. thank you again and keep up the good work. I will subscribe now
For increased cell life, you don't want to use 100% of the capacity. The peak and valley of the charge curve cause the most wear on the cells. So if you trim 5-10% off the top and bottom you get extended life. So if the cells will go as high as 3.65, trim that to 3.6 and if the bottom is 2.8, maybe bring that up to 2.9 or even 3.0v. You would still use 80-90% of the capacity, but you'd get another couple years of use out of those cells.
Good project bud, that's not a bad value for the battery with knowing what's inside. I recently bought a premade lithium battery from amazon that was suppose to be a drop in replacement for my motorcycle, received it and it felt very heavy for a lithium battery, pulled it apart to find it was made up of used 18650 cells with 4 different model cells in use inside and had no internal bms at all, just lots of snot covering everything to keep everything glued together.
I was going to buy one and once I saw the prices I laughed my ass off. It's bad enough the raping they do to you for a damn lead acid bike battery and I've always hated buying them so since I have piles and piles of 18650's and use them for everything I just put 2p3s together and wrapped it with some black tape, soldered it together with some 12 guage. You do know everyone says you can't solder them right? Bullshit I've soldered thousands of these things and never once had one go bad and I'm not very good with this piece of crap gun I've got and most times the battery is beyond hot and can't be touched and I've never had a problem. So I just wanted to see if it would power my klr 650 and do what it needs and it was more than enough. Considering that 18650's are free everywhere all day long you don't need a bms. I've left these things on for months in the rain, snow, in the dirt and they were most surely dead and they charge right back up everytime. Almost every single thing they ever told us about Lithium is pure lies my friend and if anyone was going to have one blow up it would have been me since I've always tried but to no avail so all I can say is you could make yourself a backup battery for about NOTHING and just get a charger circuit for 12 bucks so you can use lipo instead of lifepo and your alternator can easily handle your electricity needs. If you replace some bulbs with Led their is no reason to buy the real thing. If you truly fill the whole battery space your bike has you'll have way more than enough power and you'll never get a dead battery from flooding it or a fouled plug and that to me is so much better than lead acid since you should know if you take one below 10 volts you basically guarantee it won't be there for you when you truly need or want it as is the character of L/A junk. Bms are for suckers or large expensive projects, you could probably start your bike with just 3 18650's!! Try it if you don't believe me, wouldn't take you more than 10 minutes to make one up and see for yourself and in case you're wondering what I meant by free just t hink recycle, that is where the proven ones are with one dead cell among them and in my experience they defy all the myths the internet is full of. Peace Sizzlean
I perceive those tools to have been investments in various other projects along the way. Not many folks start with all the tools, but planning to acquire one new tool as part of my budget for each new project pays dividends for years to come! Remember to buy good tools-buy once cry once is a key learning. In many cases friends or work pals will not only lend you tools, but better, lend you their experience teaching tool best practices (keeping you from breaking their tools accidentally lol!) often for the cost of a six pack of a preferred cold beverage to be enjoyed together post-assembly! Build tool equity! Fantastic video-thank you for your time in making it David!
You know honestly I don’t remember the last time I have watched a 30min+ video but man I have really enjoyed yours I don’t own a solar panel, I don’t know the first thing about electricity or batteries but I have really enjoyed it Keep it up 👍🏼 Love from Syria 🇸🇾
The great thing is you can learn so much from his videos and the other guy (j-who) that you can start making your own battery packs. If you teach yourself basic electrical how electicity flows fom positive to negative and how to add voltage and amperage depending on serial or parallel circuits, you can learn to do everything this guy is doing for yourself and.configure batteries in way that meet your own exact needs. It's not as hard as some people think. One day as a kid, I learned electronics using an old RadioShack 100 in 1 electronic experiments set. Now I'm an adult and thanks to the encouragement from TH-cam am finding ways to creatively adapt an changing out the types of batteries various goods around the house use for 18650 packs because the limited battery types of 9V, AA, AAA, and C size conventional batteries annoyed me so much with their short lives and constant recharging or replacement. Its easier than you think. It just takes a little determination to learn what's necessary to figure things out. With TH-cam, you can litterally teach yourself anything that isn't a corporate secret.
I'm just trying to come up with a way to do this without spot welding or soldering because I haven't gotten into spot welding yet, and I don't think the heat from soldering would be good for the cells. Looking for some sort of robust holder for 32700's either available commercially or 3d-printable.
I can't believe I forgot about this diy favorite of mine from way back with the salvage car hybrid battery buid for the garage/house power bank. Or the test and trial of finding the right power inverter the solar panels and solar water heater system that was built. Man ,now finding the latest Lytham 14 volt clean diy .. nice! Ty Dave p.
The b- and b+ wire was solded on one end of the busbar instead of evenly distrubuted. I saw your previous video doing so with double copper wire as busbar but not this time
Its people like you that make youtube a great place. I know people come to youtube for different reasons, some purely entertainment, some news, I do sometimes for those reasons also. My biggest reason for coming to youtube and spending countless hours on it, is to learn from people like you, it has allowed me and millions of people around the world to watch great videos like this to learn new things that otherwise we would be clueless about. Thx for the video and clear explanations and I wish u the best in 2021!
Yeah I discovered that feature years ago when I took at look at them and said, Hmm, I wonder what these do? It's been love ever since! So handy! Just be sure to never threw the screw in accidentally from the incorrect side because if the cut-off side without the head comes out of the threaded side you will without the benefit of a head to use a standard driver on find it harder to have to remove the tail with locking pliers, just a warning...
I learned something valuable too... I always put a nut on and cut it with angle grinder then sand and clean burr and remove nut. How dumb when I have these. Thanks for the knowledge
I loved that too! I always put a nut on the bolt pre cut and by winding it off the bolt you rethread the thread, if that makes sense. It does work, but this is so much better! And cleaner too.
dont talk if you dont know what you are talking about... Only because they look like protected cells doesnt mean they are. And in fact, they ARE NOT PROTECTED.
Thank you David, alot people make comments that just rediculous and waste of time to say, instead of being appreciative of knowledge you share and time given to share with others. So thank you.
Hi David, I am from Brazil. Excellent job. Congratulations. I have just one question. Why haven't you use or connect the wires in the middle of the battery pack? Shouldn't better distribute the load and current flow in the battery? Also it would help to balance faster than what you have today. I appreciate your comments. Thanks Rodrigo
I'm liking these cells and the battery box... if you did 80 cells in the box and you did a 48v battery 16s5p you could make a nice 25ah battery for your 48 volt inverter. All you need is a 16s bms.
I am given to understand that some BMS units can work in series with others of the same or similar BMS type, so you could actually build several batteries of 12V 25AH and put them in series for either 12, 24, 36, 48, 60, or 72 volts. But check very carefully that the BMS is rated for the maximum voltage configuration!
what is it like 3-5 dollars per battery at a max of 2 amps? looks fun to do but you get more capacity buying a d8 tractor battery for less than you would making one out of these little batteries. its just not worth the time. plus a d8 tractor battery wont explode like a rocket
PROFESSOT DAVID POZ, WHAT AN AMAZING PRESENTATION, THIS IS THE BEST OF TH-cam. WORTH EVERY MINUTE WATCHING. A FANTASTIC ACCOMPLISHMENT. TRULY AMAZING & EDUCATIONAL.
Great video, clear explanations and good job overall. A few notes though. I see possibly catastrophic flaw in this design. If one cell develops a fault and causes a short then the entire block of parallel cells will discharge through the faulty cell (which could be quite dramatic). Also what is the purpose of insulating battery blocks from one another? The plates you are separating with capton - well it is two sides of the same plate...
I would have put in an active balancer, I had the same issue of High voltage disconnect, and an active balancer solved this issue. Now getting full charge in quicker
awesome build video, thanks for sharing! I've been wanting to do this type of project for a while and it's nice to see all the steps laid out. The biggest concern i had was at 12:54 where you folded over the bare metal positive onto the cells. I believe the cell housing is also the negative terminal of the cell. That means the cell insulation is the only thing preventing short circuit and fire. Personally I would put some more paper and tape to make sure there's never an issue there. Maybe you did it off camera or i missed it . I hope your battery doesn't see much vibration and stays intact! also, for those cutting threads, it's a good idea to first put a nut or 2 on your bolt. This way you can file down a taper after cutting the bolt, and any damage remaining on the threads will be repaired by the nut when you remove it. Usually you don't have too much of an issue, but adding the taper is helpful for starting the threads, especially in hard to reach places.
I posted a follow up video where I answered the top 10 questions. One of those was the positive terminal. I took it apart and added more insulation. Good catch.
@@DavidPozEnergy I'm glad you got that before it became a big problem. Awesome battery, it's a shame Battery hookup want twice the price of cells to post to Australia.
Great build! It's obvious you have a lot of experience. Two suggestions (nitpicks?), from my experience. One, is that I'd go ahead and solder those crimped terminals. I mostly trust crimped on low current, but for peace of mind I go with solder whenever it involves a high current connection. Two, excessive heat can greatly reduce efficiency. the controller will get hot, but so can the batteries themselves. You have them bundled up pretty tight, I'd consider finding a way to improve air circulation to them as well. Small opening in the case could make a world of diff to the whole thing. If it were mine, I'd probably even squeeze in a small laptop fan. Once again, great build, well presented, enjoyed the video.
Soldered connections with stranded wire are less reliable if subject to vibration. If the battery was to be used in a vehicle I would try to make good crimps only.
For the amperage you intend to pull, I strongly suggest you refold your positive terminals in the other direction, as the outside of the battery cells are actually negative if and and the insulations get damaged, so with the potential heat in real use, folding your positive wires to not touch or be in close proximity to the side wall seems to be a safer choice.
Exactly my thoughts! I really hope he had some sort of insulation in there behind the bus bar... I was waiting for one of the solder blobs to go through the cell sleeve and arc out.
I like how you suggest he fold it as opposed to just not using wide open huge rails. smaller rails, rails snapped into the structure, COVERED... nope! fold it the other way. that's worth the time!
Greetings from Russia David! I would advise you to charge the battery with a balanced charger, bypassing bms, and entrust the board only with a protective shutdown. I do not trust balancing to these boards (my personal humble opinion), and balancing is not needed every time if the cells are new and from the same batch. Good luck with your projects!
You need tape between your positive terminal and the side of your battery, which is negative. A tiny bit of rubbing and you will dead short the positive of those 20 cells to the negative of those 20 cells. A couple layers of tape and some insulating board is needed or this will one day become a bomb.
To clarify for Dave, Ecospider5 is talking about the bit at 12:55 ish where the nickel strip for the positive terminal is folded around to the side of the cells. Here the heatshink around the cells is a potential point of failure. If the strip were not folded over like that there wouldn't be an issue.
I was going to post a comment about this. This is very critical, since the nickel strip sharp edge could easily cut into the battery shrink wrap. I would try to fix this sooner rather than later. Other than that great build.
Your positive bus bar is resting up against the sides of the cells which will cause a short if it wears through the cell wraps. You should put kapton tape and/or sticky paper.
I remember when I first learned what those holes on my t-stripper were for. Before I knew what a screw cutter was I held them up to the belt sander like an ape. Amazing what you can miss when you're stupid. Nice build. Thanks for sharing.
Of coarse the phone shows a more accurate wattage, it communicates with the BMS via Bluetooth. The other Meter has resistance of the 20-22 gauge wire before it gets its information.
Nice work David but one concern I have is that you can actually buy LifePo4-batteries from sources like AliExpress that have 200 Ah with a build in BMS from a reputable source for a similar price. Also if you work with multiple cells you should explain people that it is best practice to bottomlevel(or how it is correctly named , don't remember the exact term) these cells. This is achieved most easiest by placing all cells with the negative pole on a metal plate and putting a metal plate on top of the positive poles. This way you create one giant parallel connection which will result in leveling out the small differences in charge. This will significantly extend the life of the single cells when they are seriesconnected. No cell will 'work' harder than another. One last thing, if you purchase an MMPT-inverter then things like overcharge/temperaturecontrol and sofort are all regulated by that inverter resulting in a very easy installmentprocess. It will srill require some correct programming of the MMPT ofcourse. It has to know what is connected to it(batterychemistry/charge-Amps etc.)
Man! I'm a long time motor head a don't know a whole lot about this type of stuff. That said, this is fascinating! Great work! I think I might have found a new future hobby.
"I like." (it). I like saving tons of money by buying savvily things I do not really need (or even want) every day, and that's the secret on how I end up saving 500$ a day, thank you :)
Top 10 Questions Answered here: th-cam.com/video/sPZwL1z_qxI/w-d-xo.html
How do you know that small wires inside can hold current from the batteries?
David...this is an awesome project, but u definitely know what u r doing in regards to DC currents and voltages etc and the use of meters, heating etc, what is your background, are u a technician...thks..i would love to try that set up but not understanding the principles of DC electricity, one could harm himself..thks
thanks a bunch for this quick response
Wifey wants her iPhone back...
Can I buy that battery from you? I have a back injury at the moment and can't get around to do much. I am living on my sailboat in Seabrook Texas and need a decent power supply. I would appreciate it. If you aren't using it that is?
i only missed the part where you can save 500/day :D
i know right
Lol indeed
Should these even be put in a car? 🤣
I Need to start spending $500/day so I can start saving $500/day!
It cost him $ 440, less his labour, a battery that spec, worth 900 to 1100 k, so ill assume he means, he saved 500, if he sells them for 900,he made 500,for that day project, but he should say this , tp not look click baitish
Awesome thing to build your own battery David! Amazing what you have learned about all this stuff because you were not afraid to try. Your kids are also watching and learning. They'll be awesome as well. You and your wife are great parents.
SON! probably the best presentation of any subject I have watched on u'tube! I've been to automotive and aircraft schools off and on over the 55 years in the mechanical field. I had only a couple of instructors that presented the info as concise as your did, and that's including speech delivery, clear! Thanks!
David, that was a treat to watch. Thank you so much. I really enjoyed it.
Thank you David for sharing your build video. I found it interesting and was impressed with your attention to detail. I hope your battery serves you well for a long time to come.
Just spent 40min watching a guy build a battery. Intriguing and fascinating. Learned a lot.
I’ll just buy one.
Thanks for going over this project! I always love learning about your Poz loads.
Amazing video! Thank you for sharing this with the community. Can't wait to try it out ☺️
Impressive build. Very well done. Loved the logo. I felt as if I were actually building this along with you. Very detailed and you explained the process well. Bravo!
One of the best vids on you tube. No over explanations, no poxy music in the background, well done.
I didn't realize that, but you're spot on! Really well put together indeed.
I'm sure you already know this but cells with built in battery protection circuits tend to be longer, even though they can be marked as 18650. Some of these circuits can add 5mm to the length and this may be why. If you rip the plastic wrapper off one, you might find one tacked onto the end of a cell.
I love the detailed step by step planning and assembly. Absolutely professional
For me it does not look professional due to some severe points missing:
- How to protect against short circuiting when attaching the bms
- Design flaws: the "prepared" end nickel construction has only the 8mm strips to combine the two left and right sided cell strings and those can easily provide 20 amps each, but you told us the strip is good for 5 amps. That is a severe heating source!
- Not repair-friendly: welding 20 cells makes them very hard to find broken ones and to replace them
- The welding points can heat up
- More information about the welding hardware would be desirable
- and lots more
Knowledge is priceless! I've learned so many practical stuff in this video alone that you can extend to so many other projects. Kudos to you, David. Love the the logo too ;-)
knowledge may be priceless but think of something someone learned after 5 yrs of experience and showing you when you just started to learn about it thats huge thank you for sharing tricks.
I disagree. I say this after spending ~$1000 in nissan leaf modules/lg battereis/harnesses/BMS's and all the messed up wire crimping/messed up power supplies. Even after spending hours watching these youtube videos, you still have to DO IT. That's where the rubber meets the road and you end up creating knowledge. For instance, bms's are designed to keep a cell from getting damaged...if you connect several batteries in parallel and then hook them up to a BMS, you can still damage batteries because the bms treats the group as 1 and can't tell if any 1 of them has gone below/above the set voltages, so if 1 of them goes beyond those bounds, the others will make up the difference on the top/bottom which will eventually ruin the whole group.
Well done I use to install solar systems in the 80s we used lead acid fork lift battery's. The battery banks were usually only 48 volt systems so there was not a hazard from getting shocked but a short across a battery battery bank will do severe damage to anything near by. Take every precaution to not let the positive and negative leads touch the amperage is very height and will weld and or vaporize conductors.
This was such a terrific step by step video... Thank you so much for sharing! You are a great teacher!
Thanks for your valuable input. During the next weeks I'll be busy. Your video helps us on our little island in the Pacific.
Finally a quality Lifepo4 diy batter video! I need to build a 72v version for my ebike
wow man i have never seen such a detailed build, most people will stop after the spot welding, but that final parts cost sheet is the icing on the cake.
Thanks for watching to the end.
Dude, you seriously rock! Well done DIY!
Great Job & tutorial. TIP: I use small round Molybdenum magnet discs to hold my nickle strip in place until I get it set w/a few welds.
"this will take you guys 6 to 8 hours to complete"
That's a good one.
You got it haha :D
6 to 8 hours to complete after you've done it 6 to 8 times already.
Maybe on your second one lol
@@InnovativeSustainableSolutions if u copy him it shouldnt take u any longer than that, its not that complicated or a time consuming task, unless u are not familiar with all the basics of what he did to begin with, then it may take u some time. If u are someone like me that is always messing with these types of things then it should actually take less time, its all about proper prep. Proper prep is one of the most important steps, and ultimately what saves u time. I usually write up steps and everything i need on white board, and layout everything according to my steps.This guy did all the layout and figuring out everything to do. Ur part is basically just assembly, The way I approach things is get everything together tools materals and lay them out in as needed order where possible, battery case on end, say 30 or so minutes getting everything rdy lay out ur cells and put them together that isnt a long process cut materials to length spot weld on etc.. Its easy to see what took him so long, there are a lot of extra problems to solve along with how to do the battery for video. I find most people over think most things and make it harder for themselves.
So how long would that be having to deal with 4 children 24/7 at home from 1yrs old to 6yr old...
Great video! Nice to see someone who really knows their topic well, that can explain it, & with measurements taken all along the way. Even detail on spot welder temperature is above & beyond call of duty! Thanks
Great Video. Well explained. Your patient clear approach in explaining your actions, and why, was excellent.
I think it's awesome what you did Sir keep up the good work I'll be following you. I'm in the beginning process of a shuttle bus conversion looking into lithium batteries.
You have helped to demistify a complex subject, this is a great training video
Thank you for the great video which I came across accidentally. I am sure I learned something new, you explained very well and with great camera work. you are a good teacher.. thank you again and keep up the good work. I will subscribe now
I really enjoyed the way you explained each step in your project
So glad I found your page. So much information. Thank you!!
You’ve picked up a lot of knowledge since when you started very nicely done how’s the baby doing👍👍👍👍
LOVE LOVE THE VIDEO BROTHER!! One of your best. Thanks for letting us be a small part. God Bless.
Thanks Bobby. I love your videos too.
I sure did learn a lot. I have never seen this before.
Thanks for the video.
is so pleasing to watch. great job mate
For increased cell life, you don't want to use 100% of the capacity. The peak and valley of the charge curve cause the most wear on the cells. So if you trim 5-10% off the top and bottom you get extended life. So if the cells will go as high as 3.65, trim that to 3.6 and if the bottom is 2.8, maybe bring that up to 2.9 or even 3.0v. You would still use 80-90% of the capacity, but you'd get another couple years of use out of those cells.
The profile to set the top and bottom cutoff needs to be an option within the BMS - does the BMS David installed have this capability?
Good project bud, that's not a bad value for the battery with knowing what's inside. I recently bought a premade lithium battery from amazon that was suppose to be a drop in replacement for my motorcycle, received it and it felt very heavy for a lithium battery, pulled it apart to find it was made up of used 18650 cells with 4 different model cells in use inside and had no internal bms at all, just lots of snot covering everything to keep everything glued together.
I was going to buy one and once I saw the prices I laughed my ass off. It's bad enough the raping they do to you for a damn lead acid bike battery and I've always hated buying them so since I have piles and piles of 18650's and use them for everything I just put 2p3s together and wrapped it with some black tape, soldered it together with some 12 guage. You do know everyone says you can't solder them right? Bullshit I've soldered thousands of these things and never once had one go bad and I'm not very good with this piece of crap gun I've got and most times the battery is beyond hot and can't be touched and I've never had a problem. So I just wanted to see if it would power my klr 650 and do what it needs and it was more than enough. Considering that 18650's are free everywhere all day long you don't need a bms. I've left these things on for months in the rain, snow, in the dirt and they were most surely dead and they charge right back up everytime. Almost every single thing they ever told us about Lithium is pure lies my friend and if anyone was going to have one blow up it would have been me since I've always tried but to no avail so all I can say is you could make yourself a backup battery for about NOTHING and just get a charger circuit for 12 bucks so you can use lipo instead of lifepo and your alternator can easily handle your electricity needs. If you replace some bulbs with Led their is no reason to buy the real thing. If you truly fill the whole battery space your bike has you'll have way more than enough power and you'll never get a dead battery from flooding it or a fouled plug and that to me is so much better than lead acid since you should know if you take one below 10 volts you basically guarantee it won't be there for you when you truly need or want it as is the character of L/A junk. Bms are for suckers or large expensive projects, you could probably start your bike with just 3 18650's!! Try it if you don't believe me, wouldn't take you more than 10 minutes to make one up and see for yourself and in case you're wondering what I meant by free just t hink recycle, that is where the proven ones are with one dead cell among them and in my experience they defy all the myths the internet is full of.
Peace
Sizzlean
You get what you pay for
@@sizzlean9459 : lol, just don't park, charge, or wreck it where it will burn down a house or start a forest fire.
BMS aren't really necessary. They help squeeze out that extra little bit of energy in a battery without damaging it.
Excellent presentation and contents. Well done David!
It looks great you did a great job was actually fun watching it thank you for that
Terrific project, Dave. I really enjoy learning from you.
Great video. You’re fortunate to have the extra tools ie spot welder, calipers, various meters, and torx wrenches to make this happen at that price.
My thoughts exactly, the moment I saw what he was doing...! Those will simply eat up any savings you might make in building your won batteries.
I perceive those tools to have been investments in various other projects along the way. Not many folks start with all the tools, but planning to acquire one new tool as part of my budget for each new project pays dividends for years to come! Remember to buy good tools-buy once cry once is a key learning. In many cases friends or work pals will not only lend you tools, but better, lend you their experience teaching tool best practices (keeping you from breaking their tools accidentally lol!) often for the cost of a six pack of a preferred cold beverage to be enjoyed together post-assembly! Build tool equity!
Fantastic video-thank you for your time in making it David!
Very nicely and interestingly explained, clarity and crispness is your plus points. Kudos.
Excellent instruction! Not just how, but several why's too. Thanks! You've got a new subscriber!
Cost of what you learned on this project? Priceless. ( Great video, thanks for the cost breakdown at the end.)
Mind blown I had to immediately check my wire strippers and have the same screw cutting feature I had no clue existed. Thanks for that tip!!!
Great detail guide there. Thank you very much for sharing your diy battery build. Very much appreciated for your awesome tutorial step-by-step guide.
Awesome stuff. Thanks for putting the price breakdown at the end.
You know honestly I don’t remember the last time I have watched a 30min+ video but man I have really enjoyed yours
I don’t own a solar panel, I don’t know the first thing about electricity or batteries but I have really enjoyed it
Keep it up 👍🏼
Love from Syria 🇸🇾
Same here. I know very little about these topics but he made it really interesting to learn.
The great thing is you can learn so much from his videos and the other guy (j-who) that you can start making your own battery packs. If you teach yourself basic electrical how electicity flows fom positive to negative and how to add voltage and amperage depending on serial or parallel circuits, you can learn to do everything this guy is doing for yourself and.configure batteries in way that meet your own exact needs. It's not as hard as some people think. One day as a kid, I learned electronics using an old RadioShack 100 in 1 electronic experiments set. Now I'm an adult and thanks to the encouragement from TH-cam am finding ways to creatively adapt an changing out the types of batteries various goods around the house use for 18650 packs because the limited battery types of 9V, AA, AAA, and C size conventional batteries annoyed me so much with their short lives and constant recharging or replacement. Its easier than you think. It just takes a little determination to learn what's necessary to figure things out. With TH-cam, you can litterally teach yourself anything that isn't a corporate secret.
Cool! I've been thinking about making some batteries with those, too.
I'm just trying to come up with a way to do this without spot welding or soldering because I haven't gotten into spot welding yet, and I don't think the heat from soldering would be good for the cells. Looking for some sort of robust holder for 32700's either available commercially or 3d-printable.
Ok well that didn't need to be said at all.
I can't believe I forgot about this diy favorite of mine from way back with the salvage car hybrid battery buid for the garage/house power bank. Or the test and trial of finding the right power inverter the solar panels and solar water heater system that was built. Man ,now finding the latest Lytham 14 volt clean diy .. nice! Ty Dave p.
Amazing video!!! Very professional building from this man. Thank you
What a great video! Thank you!
The b- and b+ wire was solded on one end of the busbar instead of evenly distrubuted. I saw your previous video doing so with double copper wire as busbar but not this time
Its people like you that make youtube a great place. I know people come to youtube for different reasons, some purely entertainment, some news, I do sometimes for those reasons also. My biggest reason for coming to youtube and spending countless hours on it, is to learn from people like you, it has allowed me and millions of people around the world to watch great videos like this to learn new things that otherwise we would be clueless about. Thx for the video and clear explanations and I wish u the best in 2021!
Your welcome. Thanks for checking it out, and the kind comment.
Wow what a great video I have watched your stuff for a while now and your doing great stuff.
Oh wow I really didn't know that wire strippers could do that ! I just checked mine and they have the same bolt choppers lol
Thank you 😂😂😂
Yeah I discovered that feature years ago when I took at look at them and said, Hmm, I wonder what these do? It's been love ever since! So handy! Just be sure to never threw the screw in accidentally from the incorrect side because if the cut-off side without the head comes out of the threaded side you will without the benefit of a head to use a standard driver on find it harder to have to remove the tail with locking pliers, just a warning...
I learned something valuable too... I always put a nut on and cut it with angle grinder then sand and clean burr and remove nut. How dumb when I have these. Thanks for the knowledge
I have been using my wire strippers for YEARS and have just found a new use for them. THANKS! 🤩
I loved that too! I always put a nut on the bolt pre cut and by winding it off the bolt you rethread the thread, if that makes sense. It does work, but this is so much better! And cleaner too.
Dave always has answers!
The 5 extra millimeters of size on you LiPo batteries is from the protection circuitry, you can see it as that extra wafer size on the positive anode.
Yes. He should check the specs to find out what the max sustained current draw is.
dont talk if you dont know what you are talking about...
Only because they look like protected cells doesnt mean they are. And in fact, they ARE NOT PROTECTED.
been experimenting with making these but the size of these batteries makes this so much better and reasonable to do! thanks for this video!
Seriously. Years ago I never finished cuz these products didn't exactly exist (although possible to make=more work)
And I just noticed I commented on a old comment of mine that I have no recollection...I've officially lost my mind...smh
Thank you David, alot people make comments that just rediculous and waste of time to say, instead of being appreciative of knowledge you share and time given to share with others. So thank you.
Hi David, I am from Brazil. Excellent job. Congratulations. I have just one question. Why haven't you use or connect the wires in the middle of the battery pack? Shouldn't better distribute the load and current flow in the battery? Also it would help to balance faster than what you have today.
I appreciate your comments.
Thanks
Rodrigo
I'm liking these cells and the battery box... if you did 80 cells in the box and you did a 48v battery 16s5p you could make a nice 25ah battery for your 48 volt inverter. All you need is a 16s bms.
Good point! I wonder what configuration / layout would work best for that box?
I am given to understand that some BMS units can work in series with others of the same or similar BMS type, so you could actually build several batteries of 12V 25AH and put them in series for either 12, 24, 36, 48, 60, or 72 volts. But check very carefully that the BMS is rated for the maximum voltage configuration!
what is it like 3-5 dollars per battery at a max of 2 amps? looks fun to do but you get more capacity buying a d8 tractor battery for less than you would making one out of these little batteries. its just not worth the time. plus a d8 tractor battery wont explode like a rocket
Great video Dave, very easy to follow. Nicely Done!
Amazing work, love it. "Going through my pile of random screws" competely bought me lol.
Instead of adding those spacers to two sides I think it would have been interesting to add thin spacers on all four sides to let a little air vent
PROFESSOT DAVID POZ, WHAT AN AMAZING PRESENTATION, THIS IS THE BEST OF TH-cam. WORTH EVERY MINUTE WATCHING. A FANTASTIC ACCOMPLISHMENT. TRULY AMAZING & EDUCATIONAL.
You make it easy to understand and follow along thank you
Impressive!!! Your attention to detail is so good I can see Howie Mandel pop up and say "You can do iiiitttttt." 😃
Great video, clear explanations and good job overall. A few notes though. I see possibly catastrophic flaw in this design. If one cell develops a fault and causes a short then the entire block of parallel cells will discharge through the faulty cell (which could be quite dramatic). Also what is the purpose of insulating battery blocks from one another? The plates you are separating with capton - well it is two sides of the same plate...
I would have put in an active balancer, I had the same issue of High voltage disconnect, and an active balancer solved this issue. Now getting full charge in quicker
Bro your videos are the dopest
I'm learning so much from you!!!!
Excellent workmanship !
Thanks for the tips, man! My $1000/day battery habit was starting to get out of control!! ✊😅💜
Same, I'm a bit more of an extremist. This end up saving me $800 a day.
awesome build video, thanks for sharing! I've been wanting to do this type of project for a while and it's nice to see all the steps laid out.
The biggest concern i had was at 12:54 where you folded over the bare metal positive onto the cells. I believe the cell housing is also the negative terminal of the cell. That means the cell insulation is the only thing preventing short circuit and fire. Personally I would put some more paper and tape to make sure there's never an issue there. Maybe you did it off camera or i missed it . I hope your battery doesn't see much vibration and stays intact!
also, for those cutting threads, it's a good idea to first put a nut or 2 on your bolt. This way you can file down a taper after cutting the bolt, and any damage remaining on the threads will be repaired by the nut when you remove it. Usually you don't have too much of an issue, but adding the taper is helpful for starting the threads, especially in hard to reach places.
I posted a follow up video where I answered the top 10 questions. One of those was the positive terminal. I took it apart and added more insulation. Good catch.
@@DavidPozEnergy very good to hear! Also thank you for teaching me/ reminding me to always read the pinned comments!
@@DavidPozEnergy I'm glad you got that before it became a big problem.
Awesome battery, it's a shame Battery hookup want twice the price of cells to post to Australia.
YOU ARE REALLY AMAIZING BRO...
Greit job, thank's for taking your time to make a video, about how you did it.
Great video! Never knew that wire strippers also cut screws. I've always wondered what it was for, but I never looked into it.
that was new for me to
I was thinking “and that it the think I’ll take away from this video”, when I got to that part.
His strippers have threads, too, to hold the screw being cut more securely. Mine doesn’t.
Great build! It's obvious you have a lot of experience. Two suggestions (nitpicks?), from my experience. One, is that I'd go ahead and solder those crimped terminals. I mostly trust crimped on low current, but for peace of mind I go with solder whenever it involves a high current connection. Two, excessive heat can greatly reduce efficiency. the controller will get hot, but so can the batteries themselves. You have them bundled up pretty tight, I'd consider finding a way to improve air circulation to them as well. Small opening in the case could make a world of diff to the whole thing. If it were mine, I'd probably even squeeze in a small laptop fan. Once again, great build, well presented, enjoyed the video.
Soldered connections with stranded wire are less reliable if subject to vibration. If the battery was to be used in a vehicle I would try to make good crimps only.
Beautiful! Thanks for sharing!
I'm digging that solder tip. Looks like it was once a flathead.
For the amperage you intend to pull, I strongly suggest you refold your positive terminals in the other direction, as the outside of the battery cells are actually negative if and and the insulations get damaged, so with the potential heat in real use, folding your positive wires to not touch or be in close proximity to the side wall seems to be a safer choice.
Exactly my thoughts! I really hope he had some sort of insulation in there behind the bus bar...
I was waiting for one of the solder blobs to go through the cell sleeve and arc out.
I like how you suggest he fold it as opposed to just not using wide open huge rails. smaller rails, rails snapped into the structure, COVERED... nope! fold it the other way. that's worth the time!
Greetings from Russia David! I would advise you to charge the battery with a balanced charger, bypassing bms, and entrust the board only with a protective shutdown. I do not trust balancing to these boards (my personal humble opinion), and balancing is not needed every time if the cells are new and from the same batch. Good luck with your projects!
True!
How do you use a balanced charger with only two connectors? Wouldn't you need an additional connector after each "row" of batteries?
Agree.
Excellent Project, good luck !!
Good job, looks like you have done your research. I have found a Unibit (step bit) to be excellent for drilling thin metal.
You need tape between your positive terminal and the side of your battery, which is negative. A tiny bit of rubbing and you will dead short the positive of those 20 cells to the negative of those 20 cells. A couple layers of tape and some insulating board is needed or this will one day become a bomb.
To clarify for Dave, Ecospider5 is talking about the bit at 12:55 ish where the nickel strip for the positive terminal is folded around to the side of the cells. Here the heatshink around the cells is a potential point of failure. If the strip were not folded over like that there wouldn't be an issue.
I was going to post a comment about this. This is very critical, since the nickel strip sharp edge could easily cut into the battery shrink wrap. I would try to fix this sooner rather than later. Other than that great build.
Glad someone else spotted and reported that too! I ringed when the loaded case was manhandled over on the bench :)
I said the same. Not sure he's reading these comments though but I hope he is or he'll have a very nasty fire some day.
Your positive bus bar is resting up against the sides of the cells which will cause a short if it wears through the cell wraps. You should put kapton tape and/or sticky paper.
That's a good point, thanks.
Heat, vibrations or time, would do that. That's logical thinking @11mlger.
great job love the patience
Thanks for taking the time to video this project. New subscriber thumbs up. Cheers
I remember when I first learned what those holes on my t-stripper were for. Before I knew what a screw cutter was I held them up to the belt sander like an ape. Amazing what you can miss when you're stupid. Nice build. Thanks for sharing.
thanks for detailed video! It's bummer that customer need to pay extra $ to enable BMS config menu.
It's sad, people screw you over every chance they get a chance.
It’s Chinese, what did you expect haha
damn !! this is alot of work. Great job !!
This is EXACTLY what I've been looking for.
Of coarse the phone shows a more accurate wattage, it communicates with the BMS via Bluetooth. The other Meter has resistance of the 20-22 gauge wire before it gets its information.
most of us would be in 500 troubles a day if we took the missus iphone for several hours or days for testing
good voice and camera angle with lighting .....good video. keep them coming thanks for the effort!
Good job. Really nice clean setup
Finally a power source that can run my enormous ecig!
Nice work David but one concern I have is that you can actually buy LifePo4-batteries from sources like AliExpress that have 200 Ah with a build in BMS from a reputable source for a similar price. Also if you work with multiple cells you should explain people that it is best practice to bottomlevel(or how it is correctly named , don't remember the exact term) these cells. This is achieved most easiest by placing all cells with the negative pole on a metal plate and putting a metal plate on top of the positive poles. This way you create one giant parallel connection which will result in leveling out the small differences in charge. This will significantly extend the life of the single cells when they are seriesconnected. No cell will 'work' harder than another. One last thing, if you purchase an MMPT-inverter then things like overcharge/temperaturecontrol and sofort are all regulated by that inverter resulting in a very easy installmentprocess. It will srill require some correct programming of the MMPT ofcourse. It has to know what is connected to it(batterychemistry/charge-Amps etc.)
Nice job w/ build looks great
Man! I'm a long time motor head a don't know a whole lot about this type of stuff. That said, this is fascinating! Great work! I think I might have found a new future hobby.
i had a ebike with this chemistry, it was a good bike, good battery.
"I like." (it). I like saving tons of money by buying savvily things I do not really need (or even want) every day, and that's the secret on how I end up saving 500$ a day, thank you :)
Man, I enjoyed watching this video. Well done,