NiMh Battery Showdown

Batteries

I’ve been to talking batteries with fellow photographer Denis between shots at On the Rocks and Strobist Valley Forge meetup, and one thing we noticed was that my Energizer AA NiMh batteries seemed to wear out faster than any others. Armed with a fancy new La Crosse Technology BC-700 Alpha Power Battery Charger, I dug in to find some high-tech and low-tech answers.

This charger has a test feature, which fully charges, discharges, and recharges a battery to determine it’s true capacity. Here’s how my batteries compared to their rated capacities, all in mAh:

The high-tech answer is that my batteries have lost capacity over time, some as much as 17%! The low-tech answer is that some of my Energizers were mixed: I had low-capacity, beat down cells mixed with higher-capacity, fresher cells. It pays to read the labels and keep them organized! My other low-tech issue was using a charger that didn’t give a definitive done indicator, likely leaving me with partially-charged batteries.

The other hot topic in batteries is currently self-discharge rate: how fast a battery drains just sitting in your bag. This would require more rigorous testing than I’m up for; from online discussions, Sanyo Eneloop seems to be the favorite.

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One Response to “NiMh Battery Showdown”

  1. Tony Says:

    Thanks for the tip. I’ve actually got the family set of enenloops on order with my sisterNlaw from where she works. Hope they are as good as everyone believes them to B.