Charging Battery !

[spike0]

hi every one, iam new to this forum and new to electronics and iam here with a lot of questions, so in my series of doubts i would like to put out few questions for now!

1. how do i charge a rechrgable battery with a minimal voultage input?

2. to be more precise - i have a 3.7 v 220 mah Lithium polimer cell - i want to charge it using a 12v dc adaptor as a source - how do i do it ?

sorry folks my questions it self could be lame but i dont know where to look for answers please help me!

[audioguru]

Hi Spike,
Welcome to our forum.
Charging a lithium battery presents a severe fire hazzard if the charging is incorrect or if the charger fails. I suggest that you look at your battery manufacturer's website for their recommendations.
We have many articles in our Articles section, and its link button is at the top of this page. There are some articles about charging lithium batteries and one is here:
http://www.web-ee.com/primers/files/fsect5.pdf

[spike0]

hi audioguru,

sorry to ask this isn't lithium ion battries and lithium polymer battries coz i wen to the articles section and i see lithium ion charging requirments and i dont see any thing regrading the li-pol cells , help me please !

thank you.

[audioguru]

Hi Spike,
Please don't make 2 new topics for the same battery charger request. I posted some battery charger precautions and a circuit in your 2nd topic.

The only difference I could find between a Lithium-Ion charger abd a Lithium-Poymer charger is that the polymer battery must be charged slower, at half the current of an ion battery.

[mixos]

Hi spike0

As audioguru noticed you should be VERY CAREFULL using and charging Li-Ion or Li-Po batteries, as they can cause fire and injuries if impoperly used. First of all i suggest you to read carefully the "Panasonic Li-Ion - Precautions.pdf" i attach you to fully understund what not to do with your battery.

Then you can check "Charging Simplified for High Capacity Batteries - Microchip.pdf" that introduces a simple li-ion charger, that you could build it yourself. Have in mind that no "easy" way exists to charge your battery, you should at least use a protection IC or something.

Take care..

Panasonic_Li-Ion_-_Precautions.pdf

Charging_Simplified_for_High_Capacity_Batteries_-_Microchip.pdf

[spike0]

thanx people !
iam gonna give it a shot

[FH16]

Hi spike0.
First you must know how many cell's is your battery, then you need information from the manufacture as audioguru say allready, then try to search the net for how to build the charger (My opinion is to use a circuit with microcontroler and battery monitor IC's) and finally you must try again again you charger. Here it is an article for NiCd and NiMH batteries charger. http://www.electronics-lab.com/projects/power/037/index.html