If I change R10 to 0.025 can I get a 2A charger? 
I destroyed my charger today while trying to reduce the charging voltage.
Desoldered R6 and soldered a through hole resistor to one soldering point. While lightly pulling on the resistor to check the soldering I ripped the soldering point from the pcb. Now I can not solder anything to R6 :person_facepalming:
This PCB design is not made for any through-hole resistors. I am actually amazed you found the space to put it there.
edit: read further up, apparently some users made through hole work. all I had/could fit were SMD.
I think you are right. SMD resistors are the only resistors you can securely solder to the PCB.
That is how mine looks now. There is no way to solder anything to it anymore.
you could try to fix the board but I doubt it’ll be worth it for a charger that costs $2 on promo/after points. What does it do currently, when you switch it on? Nothing works?
Has anyone compared charging voltage of Lii-100 to Lii-100B? The Lii-100B is the one without a power bank function.
My Lii-100B charges with max voltage of 4.23, while my Lii-100 charges with max voltage of 4.25. Of course it could just be a fluke and nothing to do with it being a “B”.
I don’t know what’s happening after plugging it in and I have thrown it away already. So I can’t test it.
Maybe it has already been mentioned here and I didn’t see it. But it is said that for ever .10v less than 4.2v of the terminating voltage you gain double the life cycles. So if a battery has 500 cycles at 4.2v terminating at 4.1v should give you close to 1000 cycles and 4.0v 2000 cycles.
I have never worried about it to much as seeing how there’s always some better newer battery coming out that I just have to go buy 8 of.
After a year or two I move on to the newest battery, after all who wants to throw in a 1500mah battery in there EDC when you have a 3000mah battery, that you might be in the situation when you need the extra capacity. Just my thoughts.
Some may not buy batteries very often or wish to make them last as long as possible, If you want to prolong your battery life reduce the terminating charge voltage. It also helps to reduce the depth of discharge to prolong life. Draining a battery to the low manufacture rated level ever discharge cycle reduces its life. That rating is not a level at which you decide to charge your battery at, its a specified level at which the battery can take for the number of cycles they have specified in their data sheet. Better to pull the battery a little early and give it a charge.
Im not saying you can’t drain the battery to that point every time, you can. Just know that the battery will have a shorter life.
Sixty545 this is a very nice find and thanks for sharing. 
This is very useful info here.
Just got here looking for safe 10180 charger. That would mean <=50mA charging current ideally. I couldn’t find anything universal as most chargers for cylindrical cells have lowest setting of 100mA or higher. I was also investigating those cheap TP4056 based boards from ebay and apparently by changing resistors you can also go down to 50mA or even lower. The problem is every datasheet for TP4056 I could find specify resistors for the lowest current at 100mA. Lowering the current more would mean working outside of manufacturer specs.
That of course might work, but is not guaranteed to be stable or even safe.
I wonder if anybody had luck in identifying the chip Lii-100 uses? I would like to lower the current to ~50mA and do so safely…
Or am I overthinking this? Change it if it works and be done with it?
Can somebody more proficient in electronics comment on this aspect?
The problem with such low current might be termination behavior. For Li-Ion cells, most chargers terminate when charging current falls below 100 mA, so if you were to set charging current to 50 mA, the charger would either not start or terminate immediately. The charging logic would have to be changed to possibly something time-based instead of current-based.
Check out this thread .I used the 4056 board with a 4.35v 18650 to charge my 65mAh 10180’s.Recently,I got an Astrolux 01(I think) 10180 keychain light with inbuilt charging,and I just transfere the cells to that for charging.I’m not sure about the charging current though.
It is not really a problem, but lower termination current will mean longer charge time. The slightly higher voltage will also mean more wear on the cell.
With faulty/damaged/old cells there might be problems with leakage current, but a good cell will have a very low leakage current.
According to first post at least Lii-100 termination voltage can be changed so does this mean it actually terminate based on voltage?
TP4056 to my knowledge cannot be modded to lower the termination voltage.
Thanks for the link - very informative thread.
As to built-in 10180 chargers in all those two mode lights they use 100mA charge current so this is rather on the high side as most 10180 cells are 70-90mAh capacity (some state 100mAh but I haven’t seen any test data).
HKJ - are you saying that Lii-100 and TP4056 resistor mods are safe for 50mA?
Why this would result in higher voltage? Longer charge is not a problem as well as undercharged cells - I even prefer this for prolonging cell life. Could you explain/point to any material regarding this issue with leakage current?
The TP4056 had a build-in voltage reference that is directly used, that is rather hard to change. Any chip (or circuit) where the voltage reference usage is based on a resistor divider can be adjusted.
I thought this charger uses voltage termination only when charging NiMH cells. For Li-Ion cells, it uses current termination. Maybe someone can correct me on this.
What about decreasing the resistance value to get higher currents? I have searched in the thread but I have found no information about that, has anyone done it? Wondering if it will survive with 1.5A for example,
Just dropped by to say that, while using my (modified with a switchable :-)) voltmeter) Lii-100B to recharge a bunch of same type cells in a row, I've switched the input power supply from an old LG phone charger supply with built in cable to a Fonken QC3.0, and I've noticed a slight drop in the final cell voltage with the supply swap (2 times already). No big deal, around 10 mV or a tiny bit more of difference. Will monitor it more closely now, but looks like final cell voltage is to some extent also dependent on input voltage. 
P.S.: Nah, probably not and rather inconsequential anyway.
Sun, 02/09/2020 - 22:33
Does anybody know if the Lee-500S can also be modified to terminate at a lower voltage? I’d like to lower it by 0.05V