Question about charging two 18650 batteries

Thread Starter

Danny40165

Joined Nov 21, 2020
3
Hello! First time ever posting to a forum of any kind. I have a charger made for charging a single 3.7 volt Li-Ion battery or more than one cell could be charged but at a slower charge rate. My question is there anyway to charge the two cells ran in series as the picture I attached shows with the 4.2 volt output Li-Ion charger. I'm thinking the answer may be "NO" but I didn't know if there was a way to do it that I could not think of....(diodes added,etc.). Thanks in advance for any help I may receive!batteries.jpg
 

dl324

Joined Mar 30, 2015
16,845
Welcome to AAC!
My question is there anyway to charge the two cells ran in series as the picture I attached shows with the 4.2 volt output Li-Ion charger. I'm thinking the answer may be "NO"
You're thinking was correct. The answer is no.

I have a charger made for charging a single 3.7 volt Li-Ion battery or more than one cell could be charged but at a slower charge rate.
And charging them in parallel would also be a mistake because the charging circuitry wouldn't be able to detect the end of charge condition correctly. You'd be better off charging them one at a time and making sure that each was charged properly.
 

Thread Starter

Danny40165

Joined Nov 21, 2020
3
Hi!
That is the answer I was expecting! Thanks for taking the time to reply to my question and I will just use 2 of the charging modules I have, one to each battery.

Dan
 

Dodgydave

Joined Jun 22, 2012
11,285
You can charge more than one at a time in series with a battery pcb monitor, .. with a higher voltage.
 
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