As a follow on to this thread .: https://forum.allaboutcircuits.com/threads/1-5v-aa-li-ion-rechargeable-battery-discussion.210283/
I am looking at using the LI-Ion 18650's for higher voltage/low density purposes in portable applications.
Any experiences?
'

 

Some, what's your issues?

Like all multi-series packs, correct charging and balancing is crucial. Another key issue, particularly for high discharge or fast charge regimes, is temperature management, both in terms of monitoring and physical layout/spacing.

 

All battery packs seem to be a compromise of some sort! First, compact size versus temperature control, then power delivery versus temperature rise/control. And always the challenge of cost versus performance.

 

What sort of current are you looking for?

 

Around 3 amper/hour.

 

At what voltage and run-time?

 

~6v for 1/2 to 1H sessions at a time highest durarion I can obtain.

 

So I'd recommend a 2S3P configuration; 6 x 2800mAh cells giving a nominal 7.4v, 8.4Ah capacity which will give you up to 2.5hr down to 10% SoC.

 

The challenge of the parallel arrangement, as always, is the matching of the cell's functional internal resistance during the discharge. So you will need to consider that when arranging the cell positions in the battery pack.It can work out but it takes more effort.