Battery Problems | Tmobile MDA | draining all the way down to zero

[cooppocketpc]

I have a tmobile MDA pocketpc phone edition.

I have gone through more batteries than I think I should be going through.

Standard battery: 3.7vdc, 1250mAhLi-ion


It seems that when I mistakenly let the battery drain down to zero charge, I get a little alarm....kind of a 3 or 4 trill alarm sound signifying that the battery is drained .....and then the unit simply shuts off.

Here is the problem. These batteries that drain down that low will never again charge up even if they have only been used for a few weeks at a time.

Has anyone experienced this battery life drain and having them not charging back up again. Cost me 30.00 a shot for new batteries.


Is there a condition whereby these Li-ion batteries should never be taken down to zero...and if so...are they known to not come back up always

thanks for the help

[Janak Parekh]

In general, you never want to "deep discharge" a Li-Ion or Li-Poly battery, as it can cause permanent damage to the battery.

How do you keep on encountering this situation? In most cases, the PDA auto-shuts-off some time before the complete discharge occurs to let you recharge the unit before the battery is damaged...

--janak

[Silver5]

That really seems like more of a device problem than a battery problem. I suggest you ask them to replace your phone with a another MDA. I have run the Qtek 9100 I own down to the point at which it shuts itself off and I have not had to buy a new battery to get it up and running again.

[cooppocketpc]

Janak, thanks for the reply. Well, I just stupidly let the thing run down allthewhile not checking the battery level meter. The unit does not signify in any way it is about to cut off due to low battery power. Maybe I need to get a battery meter software program that can monitor these little guys for me.

coop

[cooppocketpc]

Oh I forgot to mention that I have had replacement batteries right back in the unit after the failure of one batttery and my MDA comes back up to speed 100% perfectly. It just seems that the particular battery drain was deep enough that a new charging session could not brinng it back up. I guess it got to 'deep down' drain or something. However, my unit works fine on a battery that was never drained

Thanks Silver and Janak...Coop

[Janak Parekh]

Janak, thanks for the reply. Well, I just stupidly let the thing run down allthewhile not checking the battery level meter. The unit does not signify in any way it is about to cut off due to low battery power.
As Silver5 implies, this is suspicious. The device should warn you about a low-battery condition, unless there is either a hardware problem that prevents this or a software problem that is confusing the device. It could be the battery, for instance; the battery is responsible for reporting its life to the OS, which then warns you when appropriate.

Somewhat aside: one strategy I use to avoid discharging is to simply recharge the unit every night. I find it much easier to remember to charge regularly. I assume your battery is lasting more than one day?

--janak

[Sven Johannsen]

Just for general info, SPB Pocket Plus has a very nice battery meter that runs across the top of the display all the time, so you always can see where you stand. I think I have seen other products that do this, but PP is what I use for that and it's other functions.

The guys are right though, the device should shut down and not let you turn it on before the battery is discharged to the point of damage. On a deep discharge, it does sometimes take a good while for it to come back. I've had one or two times in the past where I've had to leave the unit on charge for a day or so before it really acted right again. Do this with a wall charger, not a USB trickle.

Those of us who have been around PPCs for a long time rarely have issues with low batteries. We have been conditioned to NEVER let the things run down. It used to result in a day rebuilding the device.

[cooppocketpc]

Thanks Swami and Janak.

I agree with all information. I have been around PocketPC's for a while too ( HP jornada 545 days) and have never seen a battery act like this. As I purchased my MDA in February when tmobile firt got them to the market, the market was not ready with a good line of accessories. I have just recently found a battery charger on Ebay from vendor Digispeak. It is a little single cavity charger for a single battery, does not charge the PDA Unit and extra battery all in one housing....just a single battery. I don't have the unit yet as it is being shipped from Hong kong....but it should do the trick in keeping extra batteries charged up outside and in lieu of the phone housing

In addition, I will purchase a software battery monitor. That should give me some battery life insurance too.


Thanks Coop

[Silver5]

I still really think there is a issue with the phone itself. When my 9100 battery is run down completely it shuts off. All I have to do is plug it in and it charges right back up. I don't have to order a new battery or head to the store to get one. You shouldn't have to do hat either. I really suggest that you have T-Mobile check it out, probably replacing your phone, while it is still under warranty.

[jrey06]

0X
when my phoned drained for the first time In the first 2 weeks I had it I complained to tmobile and they sent me a new baterry for free
also later about the sixth week I could conect to the internet they told me to updated my firmware from the www.mytmobile.com when I did I could now connect and I had tzones whitch was incompatible on the old firmware