Strange cell phone problem with the battery
 

While working at my job, I would often put my cell phone in my small locker provided to the employees at that place (it was turned on, but put on silent). When my shift was done (My shifts are generally 4-6 hours long), I would get the phone, only to find out that the battery was really low (despite being fully charged when I put it in. In one case, I even recharged it overnight before putting it in the locker). I tried putting the cell phone on top of a folder (so that it wasn't physically touching the metal), but it still loses all its power.

Thinking the lockers might've had something to do with it, I kept the cell phone on me (we're not supposed to carry them while on duty), and left it on, but on silent mode (so any calls I get don't vibrate or make noise for me). For some reason, when I'm carrying the phone in my pocket, the battery doesn't lose any drainage (nor does it lose power while lying on my wooden computer desk). It still has three power bars on the battery icon when I'm done with my shift while it's in my pocket.

So my question here is, are cell phone batteries prone to draining if it's exposed to metal or something? I have a Sprint phone, Sanyo MM-7500, but my old cell phone before this one never gave me any battery issues. I'm just wondering if I discovered some kind of flaw in the battery, or if it's a known issue (the battery seems fine as long as I don't put it in my locker at work).

I'm thinking of emailing Sprint about the problem, but again, I'm not sure if this is a known issue already, or if I discovered a problem that they're not aware of.

Any of you ever have any kind of problem somewhat like this?

I know that my cell phone, if I'm getting shitty/no reception seems to lose it's charge faster. Like, if it keeps trying to find a good signal, the screen keeps lighting itself up, on and off, as it looks for and finds/looses a signal. Say, if I was to stick it in a metal locker where it probably would get shitty reception, it may drain it.

Now this is just my half assed observation based on my own phone. Hell, it may not even be true for me I just may seem to only notice it when I get bad reception. Either way, something to think about.

Giving Sprint a call/email couldn't hurt in the least though.

When you put the cellphone in your locker, you have placed it inside of a Faraday cage. No cellular service can get into the locker (or any other EM radiation for that matter), so it is possible that the cell phone is expending its energy searching for a network to join.

I lost my antenna and had the same problem, no service, so it goes into an analog search mode which drains it very very quickly. I believe that ElectricSheep is right, The locker doesn't allow much or any signal through it. On the bright side, I don't believe that you will need to buy a new battery.

You might find this stated in the owner's handbook for your cell phone or home cordless phone.

Batteries drain faster when the signal is weak or nonexistant. In laymen's terms, you could say its "working harder" to find a connection that whole time.

My cell phone battery use to suck ass too. I'd charge it over night, put it in my purse turned OFF before school, get out of school and turn it on, call my mom and it dies in 5 minutes and I'm NOT lying. I took it to my cell phone provider and they gave me an extended battery. My old battery was just old and it was swollen really bad too. They said it was dangerous for me to keep it cause it could explode or something. My new battery lasts DAYS without being recharged.

Litium Ion batteries only have a finite number of "charge cycles" before they go bad. After that, they just won't hold a charge at all. All of the Litium Ion batteries that I've had lost enough of their charge-retaining ability to become useless after two years.

Cool replies, yeah I think that might've been the problem (the "searching mode"). I went to the Chicago Museum of Science and Industry today, and saw that it was doing that "searching for network" thing, so just turned it off (and I have to say, I don't think I want to go back there anytime soon. It's not the museum, which was pretty cool, it was the horrendous traffic, which I'm not used to driving in, but I'm going off topic now :D).

Yeah, I didn't think anything was wrong with the battery, or else it should've kept dying even while I had it on me (and not inside a metal locker). And I'm sure that'd be an easy enough problem to solve if it was just the battery nearing the end of its life (I just got the cellphone about 2 months ago).