Solved! Laptop battery quick death

[Maxios-7]

hi, I'm having a problem with my laptop.
I bought it half year ago and it was used so its not new (brand: Dell inspiron N5010) so I tried the battery to see how it lasts (it lasted for 1.5 hours on power saver mode), so I bought a new one and after I tried it it lasts for around 2 hours.
after some months of use the battery decreased to 1 hour .. then 30 minutes.
I put back the old battery to find that it only lasts for 45 minutes ?!!
now both batteries are dead, they only last for less than 30 minutes on power saver mode, and when I try to hibernate the laptop it does not, it shut down completely instead of that.
I don't know where the problem, the battery or the charger or the laptop itself ...
also, I'm using the battery only for surfing the net or playing a video and always on battery saver mode and brightness on 0%

 

[jsmithepa]

There lots of "chinese" batteries out there, is a crapshoot.

For longevity, always get battery from the laptop's vendor.

For this particular item, is truly what you paid for.