Best compromise AA+AAA charger?

I've been using a Power2000 XP675 (from Amazon) for a couple of years. It charges AA & AAA pretty quickly, has four individual LED's 'battery charge' indicators (one for each battery loaded; they operate independently), a discharge button...plus it is dual power (110/220v) and has a nice fold-in plug for a compact design.

This is my standard 'travel charger', as I love its compact size.


However, when getting ready for last month's trip, I had concerns over the capacity of my NiMH batteries...they were getting old. So I picked up a La Crosse Technology BC-900 (also from Amazon), as it is able to charge-discharge-test batteries and tell you what their remaining capacity is. This proved to be extremely valuable, as some of my older AA's were found to be in the 'nearly dead' (<500 mA-hr) range, and were replaced.

This has instantly become my preferred use-at-home charger.

For new AA NiMH batteries, the LaCrosse came with some Sanyo 2,700 mA-hr, plus I picked up a dozen Pearstone 2900 mA-hr from B&H (PEAANM2900). It took roughly two charge-discharge cycles to condition them, and they were all reliably returning real capacities in the 2000-2400 range; FWIW, I suspect that they are discharging some within 48 hours; this is apparently a problem with the higher capacity ratings.

I don't have any need to charge 9V, so neither of these chargers has that feature; sorry.

I think that in general that the more rapid the charge, the worse that it is for the health/welfare of the battery.

Charger features vs. the above wish list:

Car Adaptor: neither

One of mine --> dual 110/240VAC power: both

9V batteries: neither

USB: neither

"Best" charger tech:
- individual cell charging: both

"Best" charger tech:
- individual LEDs: both, but the XP675 uses a simple 4 segment icon, whereas the BC-900 gives you a number (capacity value).

"Best" charger tech:
- ability to discharge: both, but BC-900 is again better (numbers are more informative than icons).

"Best" charger tech:
- variable charge rate(s): BC-900 variable (XP675 is fixed);

Charge Time <2 hours: neither, if you're measuring as a full charge on a 2000+ mA-hr cell ...or both, since a partially discharged cell does generally charge up to full within 2 hours.

In general, I've found that the highest charge setting on the BC-900 (1000mA) causes AA cells to get quite hot. Based on 'how hot does it get?' unscientific test, I'd guess that the XP675 is probably charging at 500-700mA. In general, I'm less inclined to run the BC-900 at 'full blast'.

IIRC, when I was doing break-in (full charge-discharge-recharge cycles) with the Pearstone 2900 AA's with the BC-900, it was probably taking 6-8 hours with it on its highest charge/discharge setting. Some things you just shouldn't rush.

One final comment worth noting: if I fully charge a set of batteries on a quick charger and then put them into my Hyperdrive HD80's and put it on to charge, they'll almost always take more time...often 30+ minutes. I'm not sure why, but the HD80 isn't a rapid charger, and I suspect that this has something to do with it.


My general conclusion is that I'd carry just the BC-900 if it didn't have a long cord that makes it less convenient to pack/carry. The XP675 isn't necessarily the best charger, but it is quite good and it packs very small.


-hh