li-ion battery charging
 

i have recently purchased some li-ion batteries and connected them in
parallel and series to get a rating of approx22V and 4400mAH . i am not
understanding how to charge them ,,i have a dc adapter of rating 24v
and 1.25A ,can charging from this adapter be a solution to this
problem if yes then for how much time should i charge the battery pack
..?

please reply cos this is really urgent .
any kind of information is welcomed.
thanx!

li-ion battery charging
 

wrote in message
oups.com...
i have recently purchased some li-ion batteries and connected them in
parallel and series to get a rating of approx22V and 4400mAH . i am not
understanding how to charge them ,,i have a dc adapter of rating 24v
and 1.25A ,can charging from this adapter be a solution to this
problem

Absolutely not, it *will* almost certainly destroy the cells, and they may
well explode. Do a Google search- there's plenty of info on how to acheive
what you want. IIRC, basically Li-Ion cells must be charged with both
current and voltage control. It's not too technical in theory, but you can't
just bung a constant current through them and expect them to last.

Dave

li-ion battery charging
 

On 9 Feb 2006 18:03:51 -0800, wrote:

i have recently purchased some li-ion batteries and connected them in
parallel and series to get a rating of approx22V and 4400mAH . i am not
understanding how to charge them ,,i have a dc adapter of rating 24v
and 1.25A ,can charging from this adapter be a solution to this
problem if yes then for how much time should i charge the battery pack

Assuming this is not a troll, charging of Li-Ion cells is a far more demanding
exercise than nickel-based or even lead-based cells. These cells present
substantial risks if not charged/discharged correctly.

The proper regime involves:

.. current-limited constant voltage charging.
.. monitoring of cell voltage differences in series strings.
.. provision for monitoring cell temperature to ensure it is within the "safe"
region.

In the recent past (it's probably been superseded several times over) I have
employed the Maxim MAX1737 controller chip in a commercial charger. It's worth
reading the data sheet on this device for much good information on the care and
feeding of these cells.

http://pdfserv.maxim-ic.com/en/ds/MAX1737.pdf

There are bound to be many more data sheets with similar valuable information.