How to fix high charge voltage in Liitokala Lii-100 and how to make lower charge currents

Right! Nice sum up.

You can also use this fix for the 4.35V position if you only have 4.30V cells. Remember that all voltages are changed by the same percentage.

It seems to be a good charger. I just miss lower charge currents. 0.5A is not really good for many batteries. I can only think of 18500, but for 14500 and smaller, I want 0,25A or lower.

New feature in OP. Set your own current.

Have you checked what those changes do to the NiMN charging behavior?
With an unmodified one, AAA NiMH cells get warm on the 0.5A setting.
I have no clue what method this charger is using charge NiMH cells though.

I think it is quite normal that AAA NiMH get warm at 0.5A.

I just made myself a mod with 50/100 mA charge current for charging some incoming 10180. I have no intention of using that unit for charging NiMH. Let's see what HKJ finds out about the NiMH charging method and we can act accordingly.

Excellent find on the current setting! Should be easy enough to remove R10 and swap with slider switch with different resistors, high vs low current.

(I’m too lazy to do it, pass to someone else.)

Excellent mod, now I can make a decent charger for the 10180.
Thanks!
Keith

paging RMM or anyone else in the business of improving on things …

+1

really thank you

> quite normal that AAA NiMH get warm at 0.5A.

Agree; some chargers use the change in temp., don’t know about this one.

Yeah, let’s wait on HJK. But if you do discover anything about how your modified chargers handle NiMH, info appreciated.

I’d guess it won’t make any particular difference, but WTFDoIKnow …


Alternatively: solder a 3k0 or 3k3 resistor in series with R6 (also in V-form). These values are easier to find than X MOhm resistors.

My Lii-100 examples had 4.245 and 4.238V charge voltage.

Yes, that will also do it, but it takes two solder irons and a lot of skill to unsolder R6 and get it fast away from the tip of either iron in healthy state (and find it afterwards ). But at least the board has a better support by this procedure.

I tried to charge a half full Eneloop XX, size AAA with 200mA in a unit modded for 200/400 mA. Happy to see that the charging stopped. Max voltage was 1.559V and cell voltage right after was 1.45V. The cell did not get warm.

It’s super easy with a tweezer style soldering iron (if you have one - I do) and a 2nd pair of tweezers to hold R6.

Nice!

Thank's for the link for the tweezer-iron. That is a must-have for my old hands.

Must find a vendor in CN or EU.

Anyone have any idea of the effects of 4.25V on a regular Li-ion battery?

Would it shave 5% or 10% of the expected recharge cycles? More? Less?

If it is in the 5-10% range, I think I’ll use the Lii-100 as is.

As I posted above, the 4.25V is charging voltage which is normal. The end voltage at battery is still around 4.2V.

Other chargers do this too. Charge voltage needs to be higher than intended final voltage, otherwise you cannot pump current in reasonable amount.

If you want to extend your battery life further and charge to 4.15V (for example) then you can do this procedure.

+ 1. This was my point in asking if the 4.25v was the voltage taken during the Charging process, not after from the cell’s voltage after taken off the charger after “Done”.

So this charger is just fine as it is.

That is a misunderstanding! The correct, recommended charger voltage is 4.20V and the battery normally is 4.15-4.19V right after charging. I'm sure that HKJ will support me in that