Canon 5D MK3 Battery Grip Battery Depletion Problem

[UmiKaibutsu]

I have a question about the battery grip for the mk3. It is the Canon version. I have about 28 nicads, I keep 6 AA in the extra battery magazine, although it doesn’t get used too often. I noticed that the batteries are totally depleted when I put it in the camera. This has happened 3 times now. The batteries do not totally deplete if they are simply left sitting freely, e.g. not in the magazine clip. (My current favorite storage for the batteries is one of those leather lens bags from Canon)

Put 6 Energizer, only cycled 10 times or so, under a year old for sure, into the energizer charger for 8 hours. Put them into the BG and they are all dead less than a month later. Whats up with that? I noticed that the magazine has a small area with a plastic cover held in by screws that could contain circuitry that may be draining them. Any ideas?

[neuroanatomist]

Any ideas?

The first one that occurs is, don't leave batteries in the grip if you're not using it. My LP-E6s didn't do that, but I've never used the 6-AA tray.

[Black_Dog]

I have Canon BGs for three other Canon bodies. Like you, I like to keep extra AA batteries in the extra battery magazines. I use usually use alkaline (usually) or NiMH. I've never used NiCads for this. I store the loaded battery magazines individually in the nylon bags Canon provides with the BGs. I have never noticed that they are draining out. I can think of three possibilities for why this may be happening:

1. There is a defect in your battery magazine that is causing it to short itself out
2. Something else in your camera bag is coming into contact that is drawing juice from the batteries or causing them to short out
3. One or more of your NiCads is defective

If #1 is the culprit, you should be able to diagnose it with an electrical multimeter. #3 can be tested by substituted by trying a different set of batteries. Good luck.