I will describe my li-ion configuration.
I am using this charger.
It works perfectly for me. Power is from 12V source and can charge 2S, 3S and 4S bateries though I never use it for 4S, only 2S and 3S. For charging use computer motherboards contacts for speaker, hdd led etc. Wires are going directly to cell contacts, not via bms.
I will make some photos and post them in new post.
NEVER, NEVER, NEVER use li-ion without BMS