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.

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...

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.

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).

Don't buy cheap ones

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

benp1 wrote: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?

They hold their charge longer when not in use.

Zippy wrote:They hold their charge longer when not in use.

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

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

Yeah, marginally

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

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

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

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).

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

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.

Eneloop are they made by Panasonic?

Yup, Panasonic/Sanyo