Solved! Laptop battery problems

richmone73

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May 6, 2010
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Ok guys so i have a gateway mx7515 laptop. the battery will no longer display the correct charge and will not charge at all. It just continues to display a charge level of 34% but really isn't charged at all because the laptop doesn't run at all with just the battery. This is with a new powersupply within the last year and a new battery in Jan 09.

So is this just a simple battery replacement?
is there a charging circuit in the laptop that i may need to worry about being bad also?
or is this also a power supply issue?

thanks for all the help you guys give.

ER
 
Solution
It sounds like it is a bad battery. Check and see if the battery is still under warranty so you do not have to pay anything for a replacement. Otherwise than that, your probably going to have to buy a new one.

RetiredChief

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Feb 22, 2007
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You can try - turn off all battery monitoring and then Power off, charge for approx 30 mins. with battery in and power pack connected Turn laptop on and re-enable monitoring and check status. SEE if % charged has changed.

The charge circuit is in the laptop. A typical li-ion battery is 10.9 volts, the power pack is generally rated at 19 V @ 4 Amps.
To find out if the problem is the laptop or the Battery you would have to put a new battery in. To verify the charging circuit is working, you would leave the system on for at least and hour on battery mode. Then check to see (1) if the battery will charge and (2) how long does it take to recharge, If it does not charge, or charges much to fast (Don't know what is too fast), or the battery get too hot - the problem is the charging circuit.

Charging:
The charging circuit should limit the voltage to approx 12 V (10% greater than the rated voltage and charging current chould not exceed 3.2 Amps ( rated output current for the battery pack x 0.8). Normally the charge current will only be about 2 Amps to 3 Amps and tapper off as the battery approaches 100 % charge. At 100 % charge the current should drop to approx 100 -> 200 milliAmps or cut off.

Li-ion battery (for a 6 cell pack @ 10.9 V):
2 sets of 3 cells connected in series connected in parallel. Each cell approx 3.6 V, 3 x 3.6 = 10.8V. The two sets are connected in parallel for current.

If you have a DVM you could measure the battery voltage. If the voltage is below 7.5 V the battery can not be recharged with the normal charging circuit. A reading of 7.3 could olso indicate that one cell in the battery pac has shorted out.

If nothing to lose ( can not return battery for a refund) and as a LAST RESORT. you could short the battery out - CAUTION JUST SHORT FOR LIKE 1/2 SECOND, leaving the short on for longer like 5 secs could cause the back to explode!!!
 
Is the replacement battery one of the no-name Chinese made ones? They have a reputation for working OK for a bit, usually 6 months, then dying. Most batteries are only warrantied for a year, so you are probably out of luck with getting a new one for free.

Your laptop model may come with some sort of battery conditioner/testing software, check it's driver web page. Run that and see if it will communicate with the battery properly.
 
G

Guest

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If convenient, It's good idea to put the new battey into another laptop to check if the battery is fine.

1, If you are unable to start the machine normally with the battery, please check whether the battery is put well, try to update the BOIS version or change the power options

2, Please disconnect the AC adapter and use your laptop until it itself shuts down, and using original gateway adapter to charge the new battery for 12 hours( Ignore LED status)

If the problem persists, i think you need a new battery for your laptop mx7515
http://www.cheap-laptop-batteries.com/laptop-battery/gateway-li4402a.htm
img.php

 

richmone73

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May 6, 2010
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Thank you all for your suggestions and advice,

I went ahead and gambled on buying a new battery. and it was the problem. The new battery charges and works great. I ended up getting it cheaper from a different vendor though that buy.com found in Illinois. the battery is new and in retail box packaging from AGPTEK.com Well thank you again for your input.

However now my lcd for the same computer is dead. I changed the inverter board and it is still very dark and barely visible so i think it is the actual backlights themselves that are bad. but i can still use the laptop with an aux monitor hooked up to the vga out connection. I will prob not try to fix this newest development and just save for a new laptop.


Thank you,

Eric Richmond