Homebrew Lights/Batteries/Charger
(Archived from 2002)

Homebrew Lights

The batteries and charger for my Nightsun lights died.  Maybe that had something to do with leaving the battery and charger plugged in the wall for the whole summer....

I found out it was a lot cheaper to make my own water bottle battery and smart charger - about half the price as buying them retail.  

The water bottle battery has 10 NiCd "C" cells, stacked in 5 groups of 2 inside the bottle, all wired in series.  The tricky part was getting all of the batteries inside the narrow bottle opening - the secret was to have enough wire between each group of 2, so that each group could be fished inside the bottle one by one. 

The DeWalt power tool charger modification took only five minutes.  The hard part was finding the right model on E-bay!

Here are some some pictures of the old battery and the innards of the DeWalt power tool charger I modified:

Many thanks to the folks on the bikecurrent e-mail list for their advice.  Much of this advice is summarized in the links below, which is why I don't go into the details of the modifications.

Copyright
Page Last Edited (though probably not for content): 14 September 2010