Laptop battery defect?

I have a laptop from Lenovo (Lenovo Ideapad c340) and I'm a little unsure about the battery. I have had the laptop for about 9 months and it only has 82 charging cycles. In the new state, the battery has 45 Wh, but now only 40 Wh. Is it normal that it lost 5 Wh in just 82 charging cycles?

In general, it never lasted very long and lost charge even when it was shut down.

Do you still have warranty on your laptop

Yes👍

Then send it back and they'll get a new one or the battery will be replaced

Unfortunately, as devices with guaranteed wear and tear, batteries are usually excluded from guarantees and warranties. A complete failure would have to take place in the first few months, so that one can hope for an exchange. Not every battery is the same, and fluctuations in capacity and measurement accuracy are normal due to the design.

The accuracy only becomes more precise with increasing use. And a performance loss of 10% is not uncommon after less than a year, even with moderate use, depending on the type of use, storage and environmental influences.

The loss of capacity is rather normal for a battery that is used frequently. 85 charging cycles only reflect that in terms of total capacity, but not the many micro-charges in which the battery is heavily closed because it may have been charged at 70% remaining capacity. This puts a huge strain on a battery.

If it also noticeably discharges when you - supposedly - shut it down, first check your Windows energy saving settings. Maybe your Windows is in a sleep mode, and just claims to shutdown. Of course, this continues to eat some electricity when it is "switched off". Usually, the power button will continue to flash if your laptop has an LED for it.

Shutting down is not the same as shutting down. There are several "state levels". Windows 10 tends to use a Hybernation Mode in a standard installation (Shutdown S4 mode) which continues to draw power, especially to supply USB devices with power when switched off. You can prevent this in the shell with this command, then your PC makes a real S5 shutdown and no longer uses electricity until you switch it on:

powercfg / hibernate off

So before I charged the battery, I always waited until it had only around 10%. I don't use the laptop that often either, so the 82 cycles are more the days it was in use 😂

I have now looked at the warranty options at Lenovo and it says that the replacement of the permanently installed battery is also secured.

I know at least for smartphones with lithium ion batteries that it is recommended not to discharge batteries below 30%, and not to start charging if the battery still has more than 70%. Having a permanent hang on the river shouldn't be that good either. Not as bad as it used to be, since the charging electronics have become more considerate.

I hardly think that you can get a warranty on the battery condition. Batteries are usually excluded from the device guarantee because they are wearing parts. Often you get a 6 month warranty on wear parts, but you are over 9 months.

As I said, from my experience 5 KW loss after 9 months is not alarming. Batteries that are really damaged, or are completely through, will not lift 30 minutes after full charge even without load. And wear and tear is normal, especially at the beginning, the effect is more noticeable.