Railfan Technology > Rechargeable batteries for new scanner have short lives

Having issues with the battery life with my new Uniden BC125AT.  Hopefully a TO member who has advanced knowledge of such issues can help. The scanner works fine. 
The issue I am having is the life of the rechargeable batteries.  I purchased two sets of Duracell AA rechargeable batteries and charged these batteries and the set of the off-brand batteries that came with the scanner for 14-16 hours.  When I installed the newly charged batteries they went dead in about three hours of use.  All six of the batteries died in about the same three hours of use.
Three hours is a short time for batteries to die.  The rechargeable batteries in my previous Uniden scanner lasted about eight to nine hours.  They were Duracell of the same capacity.  They took only three hours to charge completely, not the 14-16 hours with my new scanner. 
Should I buy a battery recharger that will charge quicker?
I have done some research and the rechargeable batteries that I purchased and the ones that came with the scanner are NiMh and are rated at 2500mAh.
Are there longer lasting double A batteries available?
Any suggestions will be very appreciated.
 

Had the same problem same scanner.What works for me is Panasonic eneloop batterie.Comes with a charger and four batteries P/N is BQ-CC17.
HTH
Steve

Thanks.  How long do your batteries last now?

Check to see that the battery switch inside the battery compartment is set to Ni-Mh.  When set to Alk, the batteries won't charge, and the low battery indicator will be uncalibrated.

Batteries last about 8 hours.They do take awhile to recharge.
Steve

There are differences in rechargeable batteries, Make sure you are using the correct ones.

As above, another vote for Panasonic eneloop batteries, and using a dedicated charger (i.e. not re-charging the batteries while they are still in the radio).  Can typically get 8-9 hours or more on my BC125AT before the annoying low-charge beep begins.
GK



Edited 1 time(s). Last edit at 02/14/23 14:37 by TheNavigator.

I have used the EBL 2800 mAh NiNh batteries from Amazon and I get about 8 hours on them.  I have been using them for about 11 months.

I also select 14 hrs for the charge time on the scanner.

Aren't rechargeable batteries supposed to be COMPLETELY DEAD before being recharged, in order to get a full charge and longer life in the scanner?  Remove nearly dead batteries from the scanner and put them in a flashlight, turn on the flashlight for 12-hrs and you will have completely dead batteries, then recharge them.  I gave up on rechargeable batteries years ago, after finding out that good "one use" batteries were much more reliable and less time consuming.

lynnpowell Wrote:
-------------------------------------------------------
> Aren't rechargeable batteries supposed to be
> COMPLETELY DEAD before being recharged, in order
> to get a full charge and longer life in the
> scanner?  Remove nearly dead batteries from the
> scanner and put them in a flashlight, turn on the
> flashlight for 12-hrs and you will have completely
> dead batteries, then recharge them.  I gave up on
> rechargeable batteries years ago, after finding
> out that good "one use" batteries were much more
> reliable and less time consuming.

No!  That applied to old, Ni-Cad cells, but it will cause premature death for modern Ni-Mh.

Uniden BC-125AT Scanner - A cautionary tale (trainorders.com)

Thanks for the responses, very helpful.  I will try these techniques.

As I posted in the linked post, I do not recommend charging any rechargeable batteries in the BC-125AT.  I'm still using that scanner today, but I always remove the batteries and recharge them on a dedicated charger.  As to how long batteries will run on a charge, that can vary considerably by brand of battery.  I have decade-old (made in Japan then) Energizer rechargeable batteries that will run longer in the radio than some near new Amazon batteries.  Also, scanners (and two-way radios) use relatively little power in standby or scan mode, but the current usage increases dramatically when the radio is producing audio--say going from 0.05 watts to 0.5 watts of current usage.  So, if my BC-125AT is just running in scan mode with little voice traffic, the batteries can last up to 8 hours before needing recharging, but if there is significant audio output happening, the batteries may need recharging in as little as 4 hours.  Most battery life between charge specs for commercial two-way radios assume the "90%-5%-5%" rule--that is, 90% of time on standby, 5% receiving audio, 5% transmitting.  As for power consumption, most commerical two-way portable radios consume about 0.05 watts in standby, 0.8 to 1.0 watts in audio output, and 5.0 watts in transmit.  Most commercial two-way portable radio batteries (depending on battery capacity) are rated at 8-14 hours of use at the duty cycle between recharges when the batteries are operating in normal (not cold) temperatures.  And, yes, with the BC-125AT (and my commercial portable radios, as well), I carry extra fully-charged batteries with me all the time when railfanning.



Edited 1 time(s). Last edit at 02/17/23 09:23 by WW.

lynnpowell Wrote:
-------------------------------------------------------
> Aren't rechargeable batteries supposed to be
> COMPLETELY DEAD before being recharged, in order
> to get a full charge and longer life in the
> scanner?

To add to radar's comment above...

Nickel-based rechargeables (NiCd and NiMH) had to be discharged and "cycled" to minimize the memory effect mentioned elsewhere. This was especially true for NiCds going back 30 years ago. Memory effect gave the perception of NiCd batteries "losing" its capacity, but the discharge cycling to mitigate the memory effect prolonged their useful life.

Chemical compositions of newer NiMH batteries improved enough that memory effect became rare, and complete discharging was no longer necessary. But NiMH designed to deep discharge (radio-controlled applications) seem to handle complete discharging just fine.

Lithium-based rechargeables (Li Ion, LiPO (Lithium Polymer)) are where you must avoid discharging completely, which will lead to chemical breakdown that will shorten usable capacity relatively quickly.

I have still-functioning NiCds, NiMHs, Li Ion batteries for my retro-computing hobby, which are ~20 years old. They obviously don't hold 100% capacity due to age, but they are good enough for 70-80% capacity at least. So I'm posting this based on that experience.

I recently purchased some Chinese NiMH, AA batteries with a 3,300 MAH capacity.  I have some 2,800 MAH NiMH batteries that are a decade old.  The difference in usage time in my BC-125AT before needing recharging is minimal, about 4-5 hours for either the new or old batteries  in the radio.  I also recently invested in a ZTS MBT-1 Pulse Load Battery Tester that tests both the "health" and the charged state of the battery.  This battery tester is not cheap by any means, but it gives an accurate reading as to the actual percentage of stored capacity in the battery.  I've already weeded out a couple of old batteries that a cheap battery charge indicator would show as "fully charged" that were, in fact, at only 40% of capacity after being charged for 8 hours.  The ZTS battery tester will test numerous sizes and types of batteries.  For "preppers", this battery tester is a great tool to check the condition of batteries kept on hand for SHTF scenarios.