Sony VGN-K31 Battery

Important - Please read before ordering / using your Sony VGN-K31 battery

Sony laptop batteries may look VERY similar on the outside, but the quality of what's on the inside will determine how well your Sony VGN-K31 battery holds it's charge and how long your Sony VGN-K31 battery is serviceable for. Beware replacement Sony VGN-K31 batteries that seem unusually cheap - they may contain cheap cells, not hold a charge well, have a low cycle life (i.e. the number of times that they can be re-charged), leak electrolyte or even catch fire!

All our batteries are CE certified. Most of our batteries contain Panasonic or LG cells, - these manufacturers are constantly improving them as newer technology becomes available. Our units often outperform the original battery, in terms of capacity (4000 mAh) and cycle life.

Our Sony VGN-K31 batteries are available at a greatly reduced price compared to the original. if you are in any way dissatisfied, you may return your battery within 7 days for a FULL refund - batteries are "chipped" to confirm authenticity.


How to charge/condition your new Sony VGN-K31 battery

It is VERY IMPORTANT that you "condition" your new battery before you use it - you must understand that ALL new batteries behave erratically until they have been conditioned properly. Many people think there is a fault when they actually have a perfectly good battery which simply requires proper conditioning.

You will receive your Sony VGN-K31 laptop battery fully discharged and unconditioned. If you turn on your Sony laptop, expecting it to work straight away you will be dissapointed. Your battery will normally take 3 or 4 charges to reach it's proper capacity and operation (sometimes more charges are needed) - until this time it is usual for it to perform strangely and hold only a little charge. Also, the LEDs and charge indicators on your charger and laptop will not give accurate information until the battery is fully conditioned - so dont take too much notice of what they do or dont indicate - just follow the instructions below.

On the first charge, your Sony laptop may indicate that charging is complete after a short period of around 15 mins. This is to be expected - simply remove the battery from your Sony VGN-K31 laptop and repeat the charging procedure. You should then use your laptop - WITHOUT the assistance of mains power, until the battery completely runs down.

Repeat the above procedure around 4 times in total over the course of the next few days - make sure you allow you battery sufficient time to get a full charge, normally an overnight charge will suffice.

When the battery is fully conditioned, the battery charge indiciators and LEDs on your laptop and charger will work reliably. Also - as the battery will be taking on much more charge, the total charge time will be longer.


Occasional Maintenance

Simply run your Sony VGN-K31 until the battery is FULLY discharged and then fully charge again. After extended periods of non-use, you should do the same. Lots of little charges followed by partial dischrage will decrease the life, performance and capacity of your battery - but in reality, this is how laptops are usually used and this may be unavoidable.


Battery "Memory" Effect

Ni-MH batteries have more of a "battery memory" than Li-ion type batteries. Battery memory effect occurs when the battery is fooled into thinking it is fully charged, when in fact it has only reached a partial charge and capacity - even though it will indicate that it is 100% charged . This is caused by only partially charging a battery over time, or only partially discharging it. This will prevent them from holding as much charge as they possibly can (i.e. the full 4000 mAh capacity) - until you recondition them again, following the instruction above for "occasional maintenance". With Ni-MH batteries, it's a good idea to repeat the process 2-3 times.