BC346XT Battery Issues

[ph03nix42]

I use the batteries that came with the 396xt and use my scanner 2 hrs a day, to and from work (yes an hour each way). I can get 2 days use out of the batteries before I have to recharge them and when I recharge I just leave the batteries in and plug it up. Never had any overheating issues or anything. Make sure that your switch inside is set to NIMH. Other than that I couldn't give you a better answer. Good luck, shes a great scanner.

 

[SCPD]

The beep I was talking about is the beep you get while the radio is on, and the batteries are low. When the scanner is on charge and turned off it shows charging. When it is done the radio shows charging complete. I have never heard the radio beep when it is done charging. I saw some 2700 batteries, but after some thinking I stayed with the 2500.

Mark

 

[MarkWestin]

20 min per charge? There is definitely a problem, but it might not be what you might think. Some questions for you.

1. How many slots (for batteries) does your charger have?
2. How many LEDs or other charge indicators does your charger have?
3. Can your charger charge 1 battery at once, or does it charge in pairs?
4. How many times have your battery set(s) been charged?
5 Have you tried your batteries in any other type of device (like a flashlight)?

There could be a few different problems that are causing your problem other than the scanner.

Mark

 

[RickS31]

The beep I was talking about is the beep you get while the radio is on, and the batteries are low. When the scanner is on charge and turned off it shows charging. When it is done the radio shows charging complete. I have never heard the radio beep when it is done charging. I saw some 2700 batteries, but after some thinking I stayed with the 2500.

Mark

It sounds like these Unidens have more battery charge smarts in them the GRE/RS units. Still may want to verify, if you can, that the charge current actually cuts off and it's not just the radio telling you that the time has elapsed and that the batteries "should or may" now be done charging. I'm only offering this because I know what most battery chargers do and the circuitry required to do it right. Just not much real estate in these things to put in those smarts.

Again, don't know the Unidens so if it actually does cutoff the charge current at the end of the timed interval, then they are safer than the units I'm familiar with (GRE/RS). Note, I said safer, not the best. Best is always an external smart charger. Externals monitor and regulate the charge current and cutoff completely if a bad cell or high current situation occurs, hard chargers don't.

 

[UPMan]

Charge current is turned off at the end of the interval.

 

[jrwarner]

346xt Battery Issues Finally Resolved

Hi jr,

I hang around on the GRE/RS sites but happened to see your post. If I may, I'd like to provide some level of input to you on battery charging, especially in the scanners.

Here's one of my posts there -

"I just want to emphasize that it is not a good idea to charge batteries in any of these scanners with the AC adapter. I've designed and built chargers and have also done a ton of research on what the designers of these rechargeables want the chargers to do to insure both full charge and full life.

Each type of battery, NiCd, NiMh and LiIon have different requirements for charge curves and discharge cutoffs. Exceeding those can result in both battery life loss as well as destruction. Included is possible destruction of the device they're in.

I decided to do an experiment with the PRO 106 with HiCap NiMh batteries. These were good batteries with only about 25 or 30 charge/discharge cycles on them. They were fully charged by an external smart charger for NiMh batteries. Within 5 hours sitting in the yellow battery carrier in the scanner attached to the AC adapter, these batteries turned extremely hot. Clearly well on their way to self destruction.

What's the message. Don't charge in the scanner! They have no smarts in them. Their whole charge process is to jam 150 or more ma into the battery no matter what. No cutoff, no overheat detection and no time limit. Bad, bad, bad.

Just a word of caution. Maybe you haven't had trouble yet but you will. Just my two cents worth."

I have no experience with Uniden. But I suspect they provide no better battery charging capability than our scanners. That is, they contain no smart circuits to properly charge these batteries and in fact can quickly destroy them. There just isn't room for the necessary circuits and heat sinking they require. My suggestion is to get a new set of 2100 maH or higher NiMhs. Charge them fully only in the external smart charger. Use them. Don't be alarmed at shorter times at the start. These batteries don't go to full capability until they've been through 5-6 charge/discharge cycles. Highly recommended you don't charge in the scanner at all. Give it a whirl. I think you'll find much better results down the pike and won't put your very expensive scanner at risk for destruction. IMHO.

Rick

Hey Rick - it was the batteries, not the scanner - you were right. I had one rechargeable go bad and it was throwing off all my charge attempts and use in the scanner. I trashed it and the problem has gone away. Thanks for your advise. Cheers!

 

[Follett108]

I didn't read every reply word for word, but have you popped the battery cover off and make sure the switch is on "NIMH". Going out on a limb here, I know that wouldn't expalain the external charging but....??? my 346 is programmed for a 8 hour charge and I get about 8-10 hours out of it.