[Elecraft] Internal Impedance of Li-Ion Battery Packs

[Ingo Meyer, DK3RED]

Hello Jim,

> ... So my
> question is, what sort of internal resistance should I expect for a battery rated like
> this? ...

...

> Here's a pack that I'm considering.
>
> http://www.batteryspace.com/polymerli-ionboxbattery111v252ah27972wh14arateli-ionwithcarsocketsmartcharger.aspx

Thats easy! Following the link the description says:
"11.1V 25.2Ah Polymer Li-Ion battery pack is made of 2 pcs of 11.1V  12.6Ah Polymer Li-ion 
battery modules in parallel connection"

Following the next link to the 11.1V  12.6Ah Polymer Li-ion battery modules says now:
"11.1 V 12.6 Ah pack is made by 3 pcs  Polymer Li-Ion cell of 3.7V 12.6Ah"

Following again the lin, at his time to the Polymer Li-Ion cell of 3.7V 12.6Ah brings the 
value:
"Internal Resistance: 14 m-ohm"

3 times 14 milliohms in each row (= 42 milliohms) with 2 rows parallel results in 21 
milliohms for the whole pack.
-- 
73/72 de Ingo, DK3RED - Don't forget: the fun is the power!
www.qrp4fun.de - dk3red at qrp4fun.de