This is a brand new Sony PCG-71311L battery. The superior cells inside this battery pack make this a longer running and longer lasting battery pack for your Sony laptop.
We use the highest quality lithium-ion battery cells that charge faster, last longer and weigh less than cheaper, lower quality batteries. Lower quality batteries can wear out in as little as 6 months. Our batteries can last up to 5 years.
An important specification to look for with rechargeable batteries is the mAh (mili amp hour) rating. This PCG-71311L battery is rated at 5200 mAh - the highest rating for a 6 cell battery pack. The higher the mAh rating, the longer your battery will run before it needs to be recharged again. There are no compatibility issues if your existing battery is rated at 4400 or 4800 mAh.
You can expect about 2 - 3 hours of run time with this Sony PCG-71311L battery when new, depending on your energy use. The higher capacity battery cells inside this cartridge have an energy capacity of 5200 mAh.