I have a questions regardin charging batteries. I have a Li-ion, 3.6V, 150 mAh battery and I am looking for a suitable charger. Unfortunately I was not able to find a compatible charger. The ones I found had a lower limit on charging current which was around 500mA. This would set my charging current to over 3C. Now this could probably work, but it would be very bad for the battery. Can you please provide me with the charger IC or some idea on how to do it with the given IC that has higher charging current. Thing that crossed my mind is to do a current divider, but that would lead to unwanted heating that I do not want.
I've used the MCP73831 which is a cheap linear charger from Microchip. They come in flavours appropriate to what features you want - in other words you get an -2AT if you want 4.20V, terminating charge at 20% of set current etc.
Choosing the one resistor correctly gives you the charge current. It's a reasonably narrow resistor range giving a current on a curve. From 10k to 60k or thereabouts gives you 100mA to under 20mA. Either side of that range, it's not really accurate. That range seems to be in the charge range you are looking for though.