Are all rechargeable AA batteries equal?

[ctznsmith]

Sorry if this is a dumb question but are some brands any better than others?

Also someone explain mAh to me. I think I know but wouldn't mind being sure.

[johnnystorm]

In theory a bigger mAh value will have a higher capacity/runtime, as with all things the quoted number can be somewhat optimistic/made up depending on how cnyical you are. Which? magazine did a test and the eneloops, maplin, energizer and 7dayshop batteries were true to rating, the 7day shops even under quoted their capacity iirc. I've got a few sets, all different brands, mainly to help distinguish which are fresh and which are dead when I inevitably mix them up in my bag...

[Templogin]

Eneloops seem to be highly thought of, but, and I hope that I am not teaching anyone to suck eggs here, the charger is really important. Get a decent intelligent charger.

[cyclingtiger]

mAh means milli-Ampere hours.

Basically it's a descriptor for batteries and other power stores that tells you the maximum milli-amps it can supply for one hour. If it were to supply that many milli-amps for one hour, it would then be either drained or significantly degraded to the point that it could no longer be considered a reliable power source for it's normal expected duty.

In order to work out how long a battery will power a given device, take the milli-amp hour rating and divide it by the power requirement for the device.

For example, if a battery were rated at 1800mAh and your GPS need 250mA to map and record a ride, you could expect the batteries to last for 7.2 hours (1800/250=7.2).

[benp1]

Don't buy cheap ones

Buy Eneloops, or 7dayshop good to go ones if you want to spend a little less

[ctznsmith]

Don't buy cheap ones

Buy Eneloops, or 7dayshop good to go ones if you want to spend a little less

Why specifically the 'good to go' ones?

[Zippy]

They hold their charge longer when not in use.

[johnnystorm]

They hold their charge longer when not in use.

And you don't have to wait thirteen hours before you can use them!

[ScotRoutes]

Don't Eneloop (and similar) batteries have less capacity than standard NIMH cells?

[benp1]

Yeah, marginally

But their capacity is not over stated. It's the fact you can charge and leave them that really makes them useful

[jam bo]

I know this isn't for rechargeables but it demonstrates the range in performance and expensive isn't always the best.

http://www.batteryshowdown.com

[rufus748]

Ive always found this site useful for battery comparison:

http://www.torchythebatteryboy.com/?m=1

He sells them on eBay as:

big_f_d_d

[Zippy]

FWIW, my battery of choice for AA rechargeables are eneloops. I also use a fairly decent charger for them. They have a decent run-time on an etrex (still showed as full at the end of 2015 BearBones 200).

[benp1]

Same. I only really buy Eneloops now - they're reasonably priced when bought in packs of 8

I can do a 2 day trip on 1 set of Eneloops in my Garmin Oregon and still have battery left, though that's with the battery saving settings on.

I tend to take a spare set anyway though

[padonbike]

The higher the maH value the better, I managed to get some AAA 1200 a few years ago and they are still working well. Try ebay and general googling.

[RobMac]

Eneloop are they made by Panasonic?

[Zippy]

Yup, Panasonic/Sanyo