Maybe 3 AW 18490's sideways with really flat tabs. A thought of mine with a ti 08100 but no I am probably building a lipo pack with an internal charger as soon as the yihi balance charger is on the market. Its a sweet lil balance charger, if its any good it should make 4 a lot series mods internal charging builds..
I love the 3s with that chip I run mine up to 9v without issue lol ok ok I run it up to 10.5v being silly sometimes ok ok 11 volts lol..
I have battle tested that chip to extremes way beyong specs lol. .18? 120W oh yeah, it supposed to stop/reset at 16A it doesn't, with a quick vape it drains the 12v batt down when I do that and the safety alarm goes off lol... Used everyday still and no drama. Its on a 12aH 12v battery..