hi guys, I measured in some months how long to charge a battery (26Ah 60 volts ) check it out.
11;40 - 17:10 18%-100% = 5:20 uur = 82%
11;45 - 16:23 40%-100% = 4;25 = 60%
10;55 - 1%-100%= uur 5:50= 99%
10;00 - 15:30 uur ( 14%-100%5:30uur )
10;41 - 16;10 uur ( 24%-100% 5:20 ) 76%
10:02 - 15:09 uur ( 20%-100% 5:10 ) 80%
11:39 - 16;55 5;17 uur( 19%-100% 5:17 ) 81%
Nice, though mine is TC (thus 30A and definitely different / longer timings).
You know it's not good to charge to 100% so often, you put your battery under stress and reduce its lifetime.
I would have liked to see on charger the percent of the battery, to stop charging when it reaches 85%. But with such a missing feature I have to rely on timings (as you did) in order to stop charging.
The charger doesn't actually charge each cell to the max 4.2V. Every time you see the battery meter reading 100%, it's actually undercharged by 0.1V per cell. So you get the benefit of the battery lasting longer that you're referring to anyway.
Can you provide a link or document where states that each cell is charged to max 4.1?
Because indeed charging to 4.1 rather than 4.2 doubles the lifetime of the battery.
Until now I charged the battery only once to 100%, rest of times I removed the charger earlier and I stopped it between 80% and 90% to protect it.
Look at your charger. It should say that it charges the battery to 69.7V. Divide 69.7V by 17 (the battery is a 17 series cell configuration) and you get 4.1V.
Seems we have different chargers... on mine the output voltage is 71.4, which devided by 17 gives exactly 4.2 V/cell:
Yeah I don't know why you have a different charger. I have two. The original charger says output 60V, but I think that's a mistake. The fast charger I bought from Outdoordreams is rated 69.7V.
This is not good... with your charger, because can charge maximum 4.1V/cell, you will never get the chance (actually give your BMS the chance) to have the cells balanced.
I know even if it is recommended to charge to 90% to double the battery lifetime, from time to time the battery must be charged to 100% to re-balance the individual cells.
I think it's a design tradeoff. 4.1V is not 90% of 4.2V, it's actually almost 98%. So the drawback that you speak of is not actually that big a problem. The benefit is that without requiring the average customer to monitor the charge and cut it off before the maximum, you get a much longer battery life and that allows you to offer a two year warranty on the battery you sell.
