My first post here & it will become clear fairly quickly that I'm no E'ee but I can put together a circuit from a schematic & understand basic electronics. Now, I want to do a simple LiFePo4 battery charger for the 26650 cells (2300mAh) . I know a bit about these batteries. I know that the ideal charging algorithm is a constant current charge until a set point (3.65V) & then constant voltage (3.65V) until the current reduces to 1/10 of the Battery C (2300mAh). I have looked at a LM317 + TL431 circuit designed for Lithium battery charging & does CC & CV charging. But the LM317 overheats & goes into thermal limitation. I didn't want to have to use heatsinks as there is not much room in the box that this charger is going into & I'm also concerned about the heating effect on other circuits in the box. I So I don't want to use a switching circuit. Anyway, I just read that if the charging current is kept to < 0.18C then when the battery reaches 3.6V it will be 99% full. Can anybody confirm this?