Liitokala Lii-M4S Terminating Charge Prematurely

My Liitokala Lii-M4S has started terminating charge early with some of my lithium-ion cells (14500 and 18650). Doesn’t seem to be any rhyme or reason to it. I decided to buy a second unit to see if the original has developed a fault and it’s looking very much like it at the moment. I took the cell in the attached photo and popped it in the new charger and it seems to be charging fine. Has anyone else had issues with these chargers?

I just power-cycled the suspect charger and it seems to be charging that 14500 now. I’m thinking it’s a firmware bug. Pretty shocking if it is.

I’ve got 4 batteries with built in charging ports. One of them gives my chargers Hell trying to charge it. If that pictured battery is your suspect try it in other chargers.

2 Thanks

I have the same problem with known good Sanyo 18650s.

Could it be high internal resistance? Poor contact with the cell or perhaps dirty contacts will influence what the charger “sees”.

Is the voltage on the screen representative of the actual voltage of the cell? There are ways of (carefully) measuring the contacts while charging.

I wouldn’t think it’s high internal resistance as the new charger does not seem to exhibit the same fault. However, the contact issues are worth investigating.

the data on the display seem to be similar to the storage mode the charger is equipped with …

Indeed, but the termination voltage varies. Sometimes it’s around 4 V.

I have this charger but my issue is the opposite, it overcharges the cells a bit, voltage depends on slots, with the power bank slot being the highest, 4.22v.

Technically 4.22v is still within tolerance.

Yes, I would personally prefer termination of 4.18V, but to say the charger “overcharges” at 4.22V is a little unfair.