Regarding your finding:
On testing, the voltage was down sufficiently to stop the keyless entry from working. So the battery lasted just 11 months.
Regarding your comment:
2025 (180mAh) would appear to be greater than that of the Panasonic 2025 (165mAh)
The capacity alone does not say anything about the pulse capability of a battery.
The explanation is quite simple.
We have different batteries for different applications for CR batteries as well as for silver batteries.
For a car key as a good example, consider that the different temperatures (summer and winter) have a strong influence on the pulse capability.
Therefore datasheets are always using room temperature as base. (Independent of the manufacturer)
Using a battery that is not designed for higher pulses may mean that not all the capacity in the battery can be used.
For pulse application like your car key we recommend to use our CR20XXMFR (165mAh)
For application without pulse demand we (like a real time clock) we recommend to use our CR20XX.MFR (180mAh)
Attached I send you the two related datasheets.
The above is a cut n paste from the Karoq forum, a reply from a battery manufacturer. I hope your milliamps aren't too high ! As said, I've ordered Panasonics, will post how I get on !
