Two of my smaller ingco battery packs have come to end. Im looking to change out the cells, there are 5 of them i see. They are low quality so want to put better quality of ones in.

I could just by a new one but for a bit less i am stuck with same low quality battery.

Does anyone know of a good battery supplier for these or similar; Samsung 25R 18650 2500mAh 20A Battery

Edited April 7, 20251 yr by sunset1

Samsung cells are the best, IMO. But they do come at a cost.
Try Samsung 18650 3500mA 3.7V Lion Battery - Micro Robotics, INR18650-35E

41 minutes ago, GreenMan said:

Samsung cells are the best, IMO. But they do come at a cost.
Try Samsung 18650 3500mA 3.7V Lion Battery - Micro Robotics, INR18650-35E

Tx saw these. They are higher capacity which i heard one should stick to similar if i remember correctly because of discharge rates

Attached is the data sheet for high star li ion cells,

they come in a 1.3ah, 1.5ah, 2ah and 2.2ah capacity, according to HIGHstar their specifications are the same just the capacity differs????

If I were in your shoes I will source Sony/Murata vtc6 cells, out of my own experience if I require a high discharge battery They are the absolute best.

another good cell is the LG chem MJ1 cell,

both of these 2 have 3000mah capacity vs the 25R with 2500mah.

dont even consider a samsung 35E they are not high power cells, any samsung cell with a R after the numerical identifier is high discharge cells, eg 15R, 20R, 25R

ISR18650-1300大配组通用技术规格书-486-2019.pdf

The primary problem is not the quality of the cells, it's that those batteries don't have balancers in them. I have considered buying ingco batteries to harvest the cells - they are currently the cheapest source locally.

20 hours ago, GreenMan said:

Samsung cells are the best, IMO. But they do come at a cost.
Try Samsung 18650 3500mA 3.7V Lion Battery - Micro Robotics, INR18650-35E

Some of those higher capacity batteries have non-standard discharge curves. From those that I have looked at, all the extra capacity was below the voltage cutoff for the BMSs I could get, so it would have been a complete waste of money to opt for them.

3 hours ago, P1000 said:

The primary problem is not the quality of the cells, it's that those batteries don't have balancers in them. I have considered buying ingco batteries to harvest the cells - they are currently the cheapest source locally.

yup, a while ago I saw 2ah ingco batteries advertised for R250.

that is R50 for a new high discharge cell. not bad...

I 100% agree with your statement that the cells are not bad quality, they just dont have a balancing circuit. And all the powertool batteries that I have salvaged from, its always either the bms or 1 cell(or 2 or 3 depends on the construction 3p5s, 2p5s, 3p10s...) that is faulty, if the battery pack have not been abused beyond recognition, and that led me to believe that the absence of a balancing circuit is causing the majority of the failures.

I add a small cheap 4.2v balancer to the packs I rebuild, iirc it only starts balancing at 4.17v at 60ma but it works, so far and it cost about R50

Interesting. Thanks for the wealth of info. Seems a shame these power tool batteries dont come with a balancer. Im a noob with this stuff so be grateful for recommendations. Only 2 cells are around 2.4v. others sre 3.6v. what would you do in this situation?

@stefan44 do you have pics of your packs with the balancer? I don't suppose you would be open to take on repairs ?

17 hours ago, sunset1 said:

Interesting. Thanks for the wealth of info. Seems a shame these power tool batteries dont come with a balancer. Im a noob with this stuff so be grateful for recommendations. Only 2 cells are around 2.4v. others sre 3.6v. what would you do in this situation?

@stefan44 do you have pics of your packs with the balancer? I don't suppose you would be open to take on repairs ?

I will manually charge all 5 cells separately to 4.2v, to balance the pack, and chances are good that the battery pack still have alot of life left in it, I would use it a couple of times and see how many charge cycles it does before the capacity becomes unusable again, if the pack goes horribly out of balance again within +-30 cycles, then will I add a balancer.

If it goes out of balance within the first or second charge/discharge cycle after manually balancing, then im afraid the balancer will be of little benefit if any. new cells is the only way forward then.

I have recovered plenty of cells that had a voltage of 2.4 volts, below 2v I chuck it in the trash, I dont even attempt to revive or capacity test.

I assumed that 2.4v is the standard low voltage cut off for majority of bms'e (actually in this case is just a battery protection board) because I also found a lot of battery packs (powertool and laptop) that the packs was dead, and inside it was one string or cell at 2.4v and the rest at 3.xx volts