P C battery failure

Hi Is there anyone how can tell my why my !yr old pc battery only works the pc for 15 mins from a 80% charge when it's serposed to last 2-3 hrs

Charge shadow - if you don't let a rechargable battery completely drain and full charge each time a small part of the capacity is lost after each cycle.

With any rechargable device I always do a complete cycle for the first 3 or 4 charges which seems to maximise capacity.
We our laptop we tend to run it on battery until it gives the final going flat warning, we then run it on the charger until we switch it off which is normally long enough for a full charge, if not I leave the charger plugged in.

With your laptop you could switch it on, let it go completly flat and then full charge it again without switching on, do this three or 4 times and it will give some battery capacity back.

my battery is on charge all of the time as i hardly use the battery

helsbyman wrote: my battery is on charge all of the time as i hardly use the battery

Thats why, your battery needs to go through charge and discharge cycles to maintain optimum efficiency, some laptops have a conditioning option in the BIOS to try and recover lost capacity .

helsbyman wrote: my battery is on charge all of the time as i hardly use the battery

It might last longer if you take it out until required and just run on the mains. :yesnod:

A lot of laptops don't work with the battery removed.

talkingcars wrote: Charge shadow - if you don't let a rechargable battery completely drain and full charge each time a small part of the capacity is lost after each cycle. .

Not really true with modern laptop batteries, that's more an older generation li-ion issue. Modern batteries are polymer based and don't have what was known as the memory effect.

However they do die if used continually on charge as they have a charging cycle, and even though your battery is fully charged and still plugged into the mains, charging cycles still occur as to prevent damage the charger allows the battery to discharge and charge up again, even though the device is saying its at full charge.

The more cycles the battery goes through, the more capacity is affected.

Battery maintenance is key, at least once a month allow the battery to run down to the point where the laptop goes into hibernation, then charge fully while the laptop is still off. This will help keep the battery in good condition for quite some time if done fairly regularly, for example my 2008 MacBook Pro is still on its original battery with 99% capacity available, however my colleagues laptop which is less than 18 months old needs a new battery. The difference is that I power cycle the battery and he just uses it all the time on the mains.

Unfortunately there is little you can do once the capacity is lost, you need a new battery (eBay has a great selection), whereas the memory effect on older batteries could be partially reversed with care and patience.