A tip on FRS Radio Batteries

Posted: Fri Oct 21, 2005 7:42 am

For those of you that use FRS Radios, with rechargable battery packs (such as the Motorola "TalkAbouts") ... how are your batteries doing?

I found that the original Motorola brand battery packs that came with mine always seemed to not hold their charges very long, but I had nothing to compare them too. Now that I've had the radios about a year, I've notice them going down-hill even more so.

I find a brand of replacement rechargables specifically for the FRS radios going under name of "Again & Again Ultra". They are great! The charge holds much longer in storage and runs long in use, than the original batteries did when they were brand new.

The best price I've found for them is at www.mdbattery.com ... about half of the list price and much less than the brand name replacements. They stock the Motorola and Cobra replacements.

[This message has been edited by EnergySaver (edited 10-21-2005).]

Posted: Mon Oct 24, 2005 7:05 am

Pardon the expresson, but I'm afraid with any NiCAD batteries, that's the "nature of THE BEAST"

.

If you have NiCAD batteries in RC Cars, Drills, or FRS RAdios, or whatever, the rule of thumb is to run them DEAD before charging. If not, then a "memory" develops and pretty soon your batteries last only 10 minutes.

Any EE's out there care to chime in? You probably know a bit more than I do

Here's a little reading material.
http://is.med.ohio-state.edu/policies/battery.htm

Mr. WISearcher

Posted: Mon Oct 24, 2005 8:14 am

You are correct about NiCad batteries.
Since I'm up on that, I tried to treat the batteries correctly, but it didn't seem to make them last. The original Motorola batteries never seemed to be that great, even when new.

These new batteries are NiMH (Nickel Metal Hydridate, might be spelled wrong) ... so they don't have the same memory problems, another plus to them. The only thing that would be even better, is if they had Lithium Ion batteries, which are even better, mainly lighter in weight.

WGA Friend Joined: 2005-09-07 Posts: 58

I'm not an expert- and not an EE. But I spend a lot of time with the model aviation hobby and I have all kinds of batteries and chargers for those batteries- NiCd, Nimh, and LiPo. There are very big differences between brands of batteries in how well they perform and hold up. There is also much debate about whether there is or isn't any memory effect with NiCds- you can find experts that will argue either way.

But I think many times memory effect is blamed for simple overcharging. More information here:

Summary from above site:
-DON'T deliberately discharge the batteries to avoid memory
-DO let the cells discharge to 1.0V/cell on occasion through normal use.
-DON'T leave the cells on trickle charge for long times, unless voltage depression can be tolerated.
-DO protect the cells from high temperature both in charging and storage.
-DON'T overcharge the cells. Use a good charging technique.
-DO choose cells wisely. Sponge/foam plates will not tolerate high charge/discharge currents as well as sintered plate.

[This message has been edited by ForeFeathers (edited 10-24-2005).]