DIY 18650 charger to increase bat life

Hey guys

I would like to bulid charger for li ion 18650 bat pack for 18 S battery

I found sweet charger on the internet



link : https://www.youtube.com/watch?v=Een3Y-1UQQk

this is only 6 S but I need to find the way to connect 3 od this units to charge 18 S pack

what I like in this charger is adjustable voltage charging for each cell 4.15 V ........to 4.2 V

charging 18650 cell to 4.15 V increase life significantly and this is what I am looking for.

maybe there is some on this forum who knows this stuff

my question is can I connect 3 of them in series and use 3 separate power suplly ? like 3 laptop chargers 19 V ?

Thanks guys

how is this charger different from any other 6s charger? i mean, i own a 608 and i love it because of it's size and portability, but it's nothing special from a charging point.
you can connect 3 of them, IF each of them has an isolated power supply and IF you have 3 power connectors and 3 balance leads. 1 for cell 1-6, the second set for 7-12 and the third one for 13-18. they act independently.

If they are electrically isolated, that will work. If they share common ground, it will not. As I understand it, a transformer will be sufficient isolation as the high voltage and low voltage side are separated. There are however, other ways of stepping down voltage.

4.15v will not give you a lot of extra battery life. The guide is a doubling for every 0.1v. So double at 4.10, quadruple at 4.0 and eight times at 3.90 (although from memory, there is no benefit after 3.93).

Depends on how precise these charger are. You may end up with very unbalanced cells if they are not

cwah said:

Depends on how precise these charger are. You may end up with very unbalanced cells if they are not

Click to expand...

the chargers are very well built. accuracy is up to par with all the others i have (icharger and stuff ...)

hey guys

I am testing now 2/24 s bms from chargery.com

after firts balance charge battery cell votage is pretty much the same from 4,14 to 4,15 V per cell
what I really like about this charger is balance current - 1,2 A
that balance nicely my diy e battery pack ( old laptops 18650)

the way to extend battery life is do not charge cell to 4,2 V

charging to 4,15 V per cell or even less ( 4,1) extend battery life and minimise degradation significantly

more test to come

Lucas