I'm impressed with these batteries for their size and considering the fact that the same amp hour battery of other models cost x4 the price . Can I use these for a solar back up system ?
Great job! question regarding the bms, daly’s data sheet states that the cut off voltages for high and low voltage is 3.75 and 2.2 v respectively, isn’t that well outside the safe voltage range? This was for the bigger models; 100 amp for example, what your bms parameters are, and can you please confirm the cutoff voltage is the same as the data sheet or is it at the more appropriate 3.65 and 2.5 v, thanks in advance.
Great questions. I'll be doing a video on this little unit soon. I've specifically made a very small lifepo4 pack so I can answer exactly these questions. Hopefully will be up in a week or two.
Its not unsafe, but it is higher and lower than most recommended max voltage cutoffs from battery manufacturers. Keep in mind a BMS cutoff is only supposed to be triggered if something else in your system fails. Charger doesn't shut off causing an overcharge state or inverter doesnt cutoff causing overdischarge state. Just two examples.
@@diyrenewableenergyelectron4996 good point, but I thought the necessity for a bms is for cell level monitoring, the battery’s voltage doesn’t necessarily need to be equal to the single cell voltage X the number of cells in series, drift in voltages can occur in few cells, even if the inverter or charger’s cutoff limit isn’t reached.
@@mohammedalsultan8915 you are correct. I was looking at it from the perspective of using brand new cells which usually stay fairly well balanced. If you are using older cells which have degraded, the voltages of individual cells can vary wildly at the top and bottom of the charge/discharge curve. I have degraded cells and it adds complications but overall I just limit my charge and discharge curve to a tighter range where the cells stay in balance.
I bought my cells via alibaba - but the links are share are the same as Will Prowse, so these are good links. I think all the cells we receive, mine included, are technically grade B cells, so they may not look perfect. In particular, I think the most common issues are scratched or blemished terminals and patches on the blue wrapping. How do you know your cells were used?
@@heinvandenbroeck3184 Unfortunately I think that is just bad luck of the draw. The terminals (I think what you call contacts) will 100% show signs of use, if only for testing. Virtually all my cells have scratching around the terminals. Dents are rare but I have seen people receive dented cells from pretty much every vendor. It could be shipping, or just the original state of the cells. I don't think it strongly suggests that they were used - probably just grade B/C cells. Depending on the denting they may be fine, or so bad you need to discard them.
Unfortunately my vendor (Shenzhen Basen) is only on alibaba, not aliexpress. In the video commentary I've linked to well respected Aliexpress vendors who sell the same cells (the same vendors Will Prowse recommends).
@@roseyguest6384 Well they all say "Grade A", but the consensus among the DIY energy crowd is that given the prices and suppliers, these are almost certainly all grade B cells. The likely only way to get legitimate grade A is to go to the actual battery manufacturer, which I don't think sells cells retail. I could be wrong about this.
Honestly I have seen allot of these capacity test video posts to be fair what I would love to see is these batteries running normal household items and for how long. Like a fridge, washing machine, a TV, some lights those sort of everyday items, in short how long a battery pack like that would run a small house?
@@howardescoffery4950 That's a good point. That said, household items can vary immensely in their power consumption, so I don't know how much individuals can learn from seeing how these cells can power my TV, for example, when their own TV might use use half or twice the power. Additionally, how long it lasts will be a function of how many cells you use. In this case I am doing a 12v 4s system, but if you did a 48v 16s, obviously it would last four times longer. In this video, I am powering my laptop and second monitor and you can see by the end, the cells lasted over three days! That is a long time, especially considering the monitor uses twice the power of the laptop.
Awesome!!! I have some on the way!!!
I'm impressed with these batteries for their size and considering the fact that the same amp hour battery of other models cost x4 the price . Can I use these for a solar back up system ?
Yes.👍 🔋
Any update on these cells for cycle life?
Ah finally😁thanks a lot
Great job! question regarding the bms, daly’s data sheet states that the cut off voltages for high and low voltage is 3.75 and 2.2 v respectively, isn’t that well outside the safe voltage range? This was for the bigger models; 100 amp for example, what your bms parameters are, and can you please confirm the cutoff voltage is the same as the data sheet or is it at the more appropriate 3.65 and 2.5 v, thanks in advance.
Great questions. I'll be doing a video on this little unit soon. I've specifically made a very small lifepo4 pack so I can answer exactly these questions. Hopefully will be up in a week or two.
Its not unsafe, but it is higher and lower than most recommended max voltage cutoffs from battery manufacturers. Keep in mind a BMS cutoff is only supposed to be triggered if something else in your system fails. Charger doesn't shut off causing an overcharge state or inverter doesnt cutoff causing overdischarge state. Just two examples.
@@TheWilltoBuild Thanks, I’ll be waiting for your videos then.
@@diyrenewableenergyelectron4996 good point, but I thought the necessity for a bms is for cell level monitoring, the battery’s voltage doesn’t necessarily need to be equal to the single cell voltage X the number of cells in series, drift in voltages can occur in few cells, even if the inverter or charger’s cutoff limit isn’t reached.
@@mohammedalsultan8915 you are correct. I was looking at it from the perspective of using brand new cells which usually stay fairly well balanced. If you are using older cells which have degraded, the voltages of individual cells can vary wildly at the top and bottom of the charge/discharge curve. I have degraded cells and it adds complications but overall I just limit my charge and discharge curve to a tighter range where the cells stay in balance.
Where did you buy these cells? I assume not from the first link. I bought cells from soonbuy (The first link) and they are used cells. NOT new!
I bought my cells via alibaba - but the links are share are the same as Will Prowse, so these are good links. I think all the cells we receive, mine included, are technically grade B cells, so they may not look perfect. In particular, I think the most common issues are scratched or blemished terminals and patches on the blue wrapping. How do you know your cells were used?
@@TheWilltoBuild They were in bad condition. Dents and the contact were obviously already used.
@@heinvandenbroeck3184 Unfortunately I think that is just bad luck of the draw. The terminals (I think what you call contacts) will 100% show signs of use, if only for testing. Virtually all my cells have scratching around the terminals. Dents are rare but I have seen people receive dented cells from pretty much every vendor. It could be shipping, or just the original state of the cells. I don't think it strongly suggests that they were used - probably just grade B/C cells. Depending on the denting they may be fine, or so bad you need to discard them.
It is possible. But Soonbuy sells these for grade A cells. Then I don't want you know what grade B cells are.
Which vendor did you get your cells from?
Unfortunately my vendor (Shenzhen Basen) is only on alibaba, not aliexpress. In the video commentary I've linked to well respected Aliexpress vendors who sell the same cells (the same vendors Will Prowse recommends).
Thanks for the quick reply. Were they grade A or grade B?
@@roseyguest6384 Well they all say "Grade A", but the consensus among the DIY energy crowd is that given the prices and suppliers, these are almost certainly all grade B cells. The likely only way to get legitimate grade A is to go to the actual battery manufacturer, which I don't think sells cells retail. I could be wrong about this.
Honestly I have seen allot of these capacity test video posts to be fair what I would love to see is these batteries running normal household items and for how long. Like a fridge, washing machine, a TV, some lights those sort of everyday items, in short how long a battery pack like that would run a small house?
@@howardescoffery4950 That's a good point. That said, household items can vary immensely in their power consumption, so I don't know how much individuals can learn from seeing how these cells can power my TV, for example, when their own TV might use use half or twice the power. Additionally, how long it lasts will be a function of how many cells you use. In this case I am doing a 12v 4s system, but if you did a 48v 16s, obviously it would last four times longer.
In this video, I am powering my laptop and second monitor and you can see by the end, the cells lasted over three days! That is a long time, especially considering the monitor uses twice the power of the laptop.
Hi
1000 watt not 1000ah
And 13.9 volts, not 13.9 amps.