Battery inexpensive

I bought the battery as a replacement for the 8 years "consumed" original battery. The battery fits perfectly.
Since this is my second laptop in my apartment, I use relatively rare, to me after my first experience somewhat lower capacity ranges considering the low price from perfect. The manufacturer calls as the original 6600mAh battery, which held by 3 hours in the new state, which reached the replacement battery is not, about 1.5 - 2 hours he keeps.
But of other Li-ion batteries as I am aware that repeated charging and discharging only brings its full capacity. But I have no sufficient experience because of low usage.
In my view and for my needs but a good, cheap buy.