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Electronics => Electronics => Topic started by: blackbeard on December 15, 2009, 09:20:38 AM

Title: battery identification?
Post by: blackbeard on December 15, 2009, 09:20:38 AM
so i have an mp3 player which seems to be suffering from crappy battery syndrom. i'd like to replace it but the thing is i have no idea what the voltage is or what type it is. if it's a lithium battery i can guess that it's 3.7v-7.4v but otherwise i have no real idea. it has no writing or numbers on it but it looks more like a sealed plastic pack of flat flexible cells rather then round cells. it's also about 2 cm by1cm by 5mm
Title: Re: battery identification?
Post by: Soeren on December 15, 2009, 11:15:41 AM
hi,

[...]  but the thing is i have no idea what the voltage is [...]
if it's a lithium battery i can guess that it's 3.7v-7.4v
So, your multimeter broke or what?
Title: Re: battery identification?
Post by: blackbeard on December 15, 2009, 12:03:05 PM
hi,

[...]  but the thing is i have no idea what the voltage is [...]
if it's a lithium battery i can guess that it's 3.7v-7.4v
So, your multimeter broke or what?


nope. it reads between .2 and .5 volts
Title: Re: battery identification?
Post by: SmAsH on December 15, 2009, 04:02:42 PM
Yeah... Then somethings wrong...
What Soeren meant was one lithium cell is 3.7v you said 3.7-7.4v...
Title: Re: battery identification?
Post by: blackbeard on December 15, 2009, 04:31:08 PM
Yeah... Then somethings wrong...
What Soeren meant was one lithium cell is 3.7v you said 3.7-7.4v...

oh i was just going by the fact that most lithium batteries i've seen are either 7.4 (2x3.7) or 3.7 for one cell.
Title: Re: battery identification?
Post by: Soeren on December 15, 2009, 04:32:36 PM
Hi,

What Soeren meant was one lithium cell is 3.7v you said 3.7-7.4v...
Lovely when other people try to formulate what you meant, disregarding any factual knowledge thereoff  ::)

blackbeard <- I simply ment to take measures, which you obviously did (but forgot to mention :P).
If it's impossible to get specs from the manufacturer or perhaps a forum about such stuff (search for your model + "battery" or something similar), try hooking it up to a variable supply.
It's most definitely a lithium based battery, as they are the ones used in such stuff and they're the only types that can be formed into any shape. I'd bet a dollar to a dime that it's a single cell lithium, so it will probably run from at least 2.5V to 2.9V, perhaps lower so start at ~2.0V and increase 0.1V for each test until it work without errors when buttons are pushed and at max. volume (don't plug it in your ears while testing this!)

If you post the make and model as well, perhaps someone here knows the model and can help you further.
Remember, the more info you provide, the greater the chance that someone can come up with an answer.
Title: Re: battery identification?
Post by: blackbeard on December 15, 2009, 05:27:43 PM
well the thing about the make and model is that it's a fake ipod knockoff and it's battery has smudged Chinese writing. i'll try hooking the mp3 up to a psu at my college tomorrow to give it a try. thanks!
Title: Re: battery identification?
Post by: Razor Concepts on December 15, 2009, 05:30:44 PM
Generally just use any similar size single cell lipo and you should be fine.
Title: Re: battery identification?
Post by: blackbeard on December 15, 2009, 06:59:16 PM
ok. does it have to be lipo or will lithium ion work? i have buckets of those
Title: Re: battery identification?
Post by: SmAsH on December 15, 2009, 07:03:35 PM
It should be the same as the old one.
Title: Re: battery identification?
Post by: blackbeard on December 15, 2009, 07:26:17 PM
It should be the same as the old one.

well it wont be :P

even if i could read the old one i doubt i could find a copy
Title: Re: battery identification?
Post by: Soeren on December 16, 2009, 01:57:57 PM
Hi,

Try looking for replacements for the equivalent iPod model - they might be the same size (although I didn't see anyone that small, but the new Shuffle has to have an even smaller battery).
http://www.ipodbatterydepot.com/ (http://www.ipodbatterydepot.com/)
http://www.uxcell.com/replacement-battery-kit-ipod-c-983_1156.html (http://www.uxcell.com/replacement-battery-kit-ipod-c-983_1156.html)