Primary Lithium battery packs?

[yazzur]

I'm a newbie on the battery issues, but I do an canoe race that is an overnight event, and need to carry enough batteries for about 8 hours. I'm using a cygolite dualcross, which requires an 6v input, and I figure (perhaps incorrectly) I need roughly about 10,000 mah.
Is there any danger in building a battery pack out of Energizer lithium L91 in 4P 4S configuration? Are there other options - other than Nimh which is heavier- that should be considered?

 

[MattK]

Do not solder on lithium cells. Building welded packs with lithium cells of any kind is only recommended for properly equipped professionals IMO.

It would be less expensive to build the pack with CR123A's in 2P 6 or 7S. Same rules apply as above. I'd recommend using an ultra premium - Duracell/Panasonic/Energizer, etc

 

[Flash_Gordon]

Welcome to CPF yazzur. What model of Cygolite Dualcross are you using? AFAIK, They run on either a 4.8V NiMH pack or a 3.8V LIon pack. In neither case would a 6V supply be proper.

Why not just get another battery pack made for your light? Two fully charged packs should give you about 8 hours on high, much more at lower settings. They are a little expensive, but in the long run will be much more economical than using any type of primary cells.

If your light is located where you can't easily reach it, the output connector of each pack can be run through a simple switch, which can be located where it is easily accessible.

Mark

 

[yazzur]

It's an older Nimh Dualcross, which I plan on upgrading with Cree Q5's. The battery pack that came with it looks like a 5 battery pack, but I guess I'd better stick a voltmeter on it to see if it's 4.8 or 6.0. I also have a model 100 Cygolite that came with a 4 -c size battery holder for alkalines, so I assumed they were both 6 volts.

I could get another battery pack, but 4 hours is stretching the one I've got, so I was looking for a little more reserve than two packs would give me. But maybe with the Cree's I won't need to run on high.

Thanks for the help.

Yazzur