Bruce Douglas wrote:

> Olin Lathrop wrote:
>
>> it's not a good idea to charge a bunch of cells in series unless they
>> are built into a pack that way.  If you have individual cells, they 
>> should
>> be charged that way.
>
>
> I was intending to make up packs of up to 8 cells in series, perhaps with
> the thermal sensor shrink-wrapped to the batteries as shown in the
> Panasonic literature.  Is there something I need to take into account?
>
> Bruce Douglas
>
Olin is right. When packmakers shrink-wrap cells in series, they have 
equipment
that carefully matches the characteristics of each cell. The main 
measurement
is impedance, but peak voltage is another. You will not be able to do 
this at home.

The reason this is needed is that unless they are matched exactly, one 
cell may be
overcharged, while another is undercharged. These mismatches weaken the pack
and reduce its life to an unacceptable level.

--Bob



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