Rechargeable batteries 'out of spec'

I'm looking at a replacement hand-held GPS unit to replace my eTrex
that has stopped working. Speaking to a local retailer I asked about
rechargeable batteries. He said that some rechargeables are bigger
than standard AA cells - 'out of spec' as he put it and may not fit.

Has anyone encountered this as a problem?

Scott

What's up with it? If it isn't physically broken it may be possible to
revive it with a master reset. See the eTrex section of this page for
details:

http://www.gpsinformation.org/dale/secret.htm


Not just rechargeables, batteries do vary in size. I'm not sure any of
them are 'out of spec' but yes they can be too large for the design of
some battery compartments.
--
Dominic Sexton

On Thu, 24 Apr 2008 22:53:05 +0100, Dominic Sexton

Thanks. I'll have a look at all of that. It is the old eTrex model.
It's is only the backlight that is not working so I will give it a go.

Get the backlight replaced. Usually it's only a couple of LEDs.

It's certainly true, NiMH batteries are normally slightly larger and
lower voltage than the equivalent alkalines, so sometimes you can find
that your equipment reports the battery as nearly flat despite it
being fully charged. Some units, e.g. my garmin etrex, has a setting
that allows you to specify the type of battery and it takes this
voltage difference into account.

Size problems aren't normal in modern gear, I've got an old Roberts
radio that is a bit of a squeeze to get the rechargables into and out
of, but normally the tolerances are high enough for it not to be a
problem.

Another thing to watch out for, if you only use your device rarely
then best stick with alkalines, they can sit in there for years and
still deliver the power, whereas NiMH batteries self-discharge and
will go flat even if not used. It takes a while, but after 3 months
or so you can lose half the power in the battery even if you've not
used it. Alkalines have a "use by" date that can be 5 or even 10
years into the future so you can pick the GPS up and it'll work even
if left in a drawer for a year or so.

Similarly, if you want to pack long-term spare batteries (e.g. ones
tha will stay in the rucksack for a long time) then pack alkalines, if
you charge some NiMH batteries and pack them as spares, there's a
strong chance that by the time you need them they'll have gone flat by
themselves or will have lost a lot of power. NiMH batteries need
frequent recharging to get the best out of them.

--
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