I was sent this 12V lithium power pack to take a look at. The owner had taken a look inside and noted that there didn't seem to be any obvious balancing or protection module for the cells. Let's take a look inside.
The measured capacity of the cells is 2,200mAh per cell, so a total of 12V at 2,200mAh or if you cheat the figures and add the cell capacities up it comes to 6,600mAh.
If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:-
http://www.bigclive.com/coffee.htm
This also keeps the channel independent of YouTube's advertising algorithms allowing it to be a bit more dangerous and naughty.
The measured capacity of the cells is 2,200mAh per cell, so a total of 12V at 2,200mAh or if you cheat the figures and add the cell capacities up it comes to 6,600mAh.
If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:-
http://www.bigclive.com/coffee.htm
This also keeps the channel independent of YouTube's advertising algorithms allowing it to be a bit more dangerous and naughty.
Dirty hack, add a 4v2 zenner and series resistor across each cell?
I have actually noticed a slight trend with DW-01 and dual mosfet protection modules
upon cutoff in series with other cells on discharge they tend to act like a reverse bias diode at a few percent of their max current allowance
so if a pack like this was, say, used on a short LED strip(the likely intended use case) it would dim down to pack-1 cell voltage(6-8.4v) and keep chugging along as long as the current remained under about 10% of the module limit
still not ideal(I would slap a cheap Schottky 10-15a reverse bias in parallel with each cell ) then use this on a voltage variant tolerant system like the USB buck port
actually with the diodes this pack would be fairly ideal for an "always on" usb port possibly even just using a 13v input with a diode and letting it stay plugged in forever and using the usb to power something like a small network switch that takes 5v
power goes out and you keep your basic access point/switch going without a fully AC UPS device
heck even the ~12v port would do that well as most "12v" network gear takes in 12v but then instantly bucks down to 5v or less
and fuck my worn laptop keyboard the K key needs to be jabbed so hard to register
I suspect that the 10S battery on my e-bike has a similar dodgy protection topology, but the battery case is so tightly packed that I can't safely remove the individual cells and restuff it. Any ideas on reconditioning the cells in situ?
Well, at least it wasn’t 3 bare cells with no protection connected to a 12v adapter, lol
I do think they’ll drift over time; have you been able to test it over these years, or did it end up forgotten on a shelf as you moved to bigger and better things?
This kind of nonsense makes me want to build power banks with all of the cells in parallel. Need a higher voltage? That's what boost converters are for…
Multiple protection curcuits are really key these days but can be lacking
In the early days of RC lipos a very good make didn't have balance leads. So after a few years of use i fitted balance leads and all 3 cells were the same voltage
Oi Clive I want my screw drivers back 🤣🤣🤣🤣🤣🤣🤣🤣 hope you are OK and safe
Those are “super”
Actually the one that reaches the high cutoff voltage first is likely the lowest capacity one, and they will all reach the low cutoff voltage at roughly the same time because even though one might only be charged to a lower voltage it would still contain the same capacity.
if not balanced and not precisely matched, I'd expect the difference in charge between the top charged and lowest charge ones to gradually increase over time until the pack stops being usable for no reason other than you can't charge the top cell or discharge the bottom cell anymore and you'd think it dead.
Had a few of these i use for bike lights (security camera battery packs). I was pondering adding some leads for balanced charging using a lipo blance charger i have. Dont want to burn the house down though. Whats the explosion risk? 😞 disapointing to know i wont get full use of the capacity if one of the cells is dipped. Any workarounds for that? (Im awful with circuits but here to learn 😅)
Who else would like to see Clive do a vid of just cells going nuclear? He can bring the containment pie dish outside.