Mar 20 2011

Homemade Flash Battery Packs

Posted by Seth in Photography

Battery packs, charging up. 2 of them with case off so you can see the guts

Charging and keeping track of 30+ rechargeable AA batteries got old for me REAL fast at the track.  Again I hit the Nerds on the Internet for a solution that would be cheap and reliable.  Quantum batteries were out of the question, I was not going to spend $250 for a battery on a $85 flash (I use cheapie Vivitar 285HV’s as slaves)


Quantum did have a product that I knew I wanted though – their battery cables. I kept my eyes on ebay and after a month I collected 4 Quantum flash cables for the Vivitar 285HV’s I use, and the Canon 430EX.  Retail price is over $50, I didn’t pay more than $20 a cable shipped.

4 AA batteries = 6 volts, so I went on the prowl for some big 6 volt batteries. Luckily for me, there is a Batteries Plus store down the street and they had quite a big selection of 6V batteries. I found waterproof plastic project enclosures and brought them with, and grabbed the battery that fit the best and also was rated high enough for my liking. 

For connections, I went over to the shack and grabbed some 4-pin plugs that also had screw locks so they wouldn’t disconnect unexpectedly on me.  Finishing up the enclosures was a fused link and a power switch.

The guts of the boxes

To charge these, I picked up 2 six-volt battery tenders and modified the packaged cable to charge 2 batteries at a time in parallel.  When they are not in the case, they sit on the charger at home, maintaining a charge.

Impressions? After 2 years of abuse, these things are still kicking.  No problems whatsoever, except for minor user problems like forgetting to plug the chargers in once!   The only time I actually killed a battery was at a two day race, I had at least 1000 full power pops on the 285HV’s before having to change to the next set.

Total cost? About $200 for four battery packs + cables.   Not bad considering I’d spend the same for ONE retail or Al Jacobs battery pack. Don’t get me wrong, those products are awesome, but I’m a DIY’er at heart.

The Quantum cable, with my end on it

Parts List (links to examples, where I can)