Etantonio
Guest
|
 Posted:
Fri Feb 11, 2005 2:08 pm Post subject:
Repair of a portable computer battery pack |
|
|
Hi,
I'm writing from a Gericom Webshox portable computer of 2001,
now the battery pack ( UN241S1 Rechargeable Li-Ion Battery Ratings:
14,4Vdc 3600mAh )
is broken son I decide to change the accumulators,
I choose 8 NiMH 3,6Ah 1,2V Accumulator.
After the substitution it still doesn't work, the charge seems to be
ok,
also is I do not understand why is used a 14 Volt supply to charge
battery pack to about 5,8V
------------------RED
+ +
- -
------------------white
+ +
- -
------------------yellow
+ +
- -
------------------green
+ +
- -
------------------black
The discharge phase is not ok, the 5,8v coming from the accumulators
seems to be blocked
in one of the two printed circuits comprised in the battery pack, so
my questions:
1) What is the job of these two circuits?
2) It is possible to connect directly the accumulators to the output
bypassing these circuits?
3) What the white, yellow and green wires are used for??
4) where I can found a scheme of a typical battery pack ??
5) why the supply is 14v to charge a 5,8v battery pack ??
Hoping in your help
many thanks ...
Antonio D'Ottavio
www.etantonio.it/en/
etantonio@gmail.com
|
|
Joel Kolstad
Guest
|
| Posted:
Fri Feb 11, 2005 2:58 pm Post subject:
Re: Repair of a portable computer battery pack |
|
|
"Etantonio" <etantonio@gmail.com> wrote in message
news:467ddbce.0502110008.257f3c2d@posting.google.com...
| Quote: | I'm writing from a Gericom Webshox portable computer of 2001,
now the battery pack ( UN241S1 Rechargeable Li-Ion Battery Ratings:
14,4Vdc 3600mAh )
is broken son I decide to change the accumulators,
I choose 8 NiMH 3,6Ah 1,2V Accumulator.
|
Umm... if your batteries ('accumulators') are 1.2V each, you're going to
need 12 of them to made a 14.4V battery pack.
| Quote: | also is I do not understand why is used a 14 Volt supply to charge
battery pack to about 5,8V
|
A back of 8 1.2V batteries in series should still get you 9.6V; at 5.8V
you've just got a bunch of dead batteries.
| Quote: | 1) What is the job of these two circuits?
|
It's usualy charging circuitry. Many laptops use lithium ion batteries that
are quite particular about how they're charged, and these days for best
battery life even NiCads and NiMhs are typically charged by 'smart'
controllers that monitor how fast the battery accepts a charge, the voltage
and slope of the voltage, etc. Additionally, usually the circuitry can
measure discharge current as well so that the laptop can estimate the
remaining battery life.
| Quote: | 2) It is possible to connect directly the accumulators to the output
bypassing these circuits?
|
It's not recommended unless you get a schematic and carefully study just
where the 'outputs' go to. However, the laptop should have a DC input jack
somewhere, and you could hook the batteries up directly to it (and provide
your own recharging circuitry) if you obtain the appropriate voltage.
| Quote: | 3) What the white, yellow and green wires are used for??
4) where I can found a scheme of a typical battery pack ??
|
I don't know.
| Quote: | 5) why the supply is 14v to charge a 5,8v battery pack ??
|
Isn't it a 14.4V battery pack?
In general, if you can get a charging voltage that's some 3-6V above the
battery voltage you can pretty much ignore have to pay close attention to
the charger's design. Bu trying to charge, say, a 13.2V battery pack with a
14V input gets a little more difficult since there's only 0.8V of drop to
'control.'
---Joel Kolstad |
|
FAQ
Memberlist
Register
Profile
Log in to check your private messages
Log in