The battery is very weak!

I still have an old Nokia in which the charging plug has X6 smartphone a strong loose contact. At first I thought the original battery of the smartphone was broken and I ordered at the company cordless King a comparable replacement battery. After that I did not notice until the loose connection. Because I wanted to use the phone even further, the batteries I decided now to load externally and was looking for a charger. In Amazon shop I ordered the charger and because it was so cheap - I ordered directly to another battery.
The charger is good, it charges the batteries quickly and displays with the LED the charge or the charge to ready.
The replacement battery is not recommended. The original Nokia batteries are probably extremely well - after comparison holds the strong 1600 mAh battery battery with King about four days life just as long as my four year old original Nokia battery. Acquired with the new charger China battery lasts me a maximum of two days useful lives only half the time. In addition, the battery passed very suddenly, so that you can refer to the battery charge indicator on the phone hardly left.
Conclusion: The charger is good the supplied battery is very weak.