JSP Powercap battery pack

[paulm]

I have one of the old JSP Powercaps, powered by 4 C cell batteries in a plastic case and attached to the helmet with the connector shown in the pic.

Nothing wrong with it, I use rechargeable C batteries in it, but the case and batteries are a bit cumbersome and heavy, so thought I would try and find a rechargeable lithium ion power pack equivalent that might ideally be a straight swap without having to mess around with changing connectors and cutting wires.

Has anyone done similar and found some parts to suit ?

I can find some battery packs online, ones for vapes seem quite common, but different connectors and no case so would have to reuse the existing bulky one.

Might be too much trouble given it works okay as is, but thought it might be worth asking

 

[SVB]

You could simply snip off existing connectors and replace. The model car industry has a whole range for swapping battlers frequently and will deal with way more current than the Powercap needs. Example here

https://www.ebay.co.uk/itm/19205674...GbiF2YoTDC&var=&widget_ver=artemis&media=COPY
in terms of lithium then match voltage and exceed mAh rating and you should be fine as you’ll be drawing quite light load to run a fan. Try and buy a battery pack pre-assembled. If not then you can solder one up and secure in a configuration that suits with a heat shrink sleeve to keep form.

 

[Sideways]

4x C cells make 6V, assuming they're in series.
Your lithium options are 1 cell (3.6V nominal, 4.2V freshly charged) or 2 cells in series (7.2V nominal, 8.4V when freshly charged). Neither of these are ideal. One being too low and the other a little high for comfort (+40%) when the cells are fresh off the charger.

You could take your chances with 2 cells, or get a cheap voltage converter (dc to dc "buck" converter with a 6V output) and feed that from probably 3off 18650 size lithium cells. They need a little extra voltage to play with but are very efficient in converting power in to power out at the chosen voltage.

Either way, I'd buy a 2 or 3 cell battery holder for the common 18650 lithiums so I could take the batteries out easily and just charge them in a li-ion battery charger (nitecore and numerous others make chargers, popular with the folk who vape ...).
That way you don't need to mess about with charging batteries wired up in a pack.