I've an Inspired Energy NI2040 10V8 spare battery that has a strange behaviour.
After several month of storage, it was indicating 0% in my Tektro scope, note that the older original battery from Tektro is still OK.
I've charged it fully (it accepted the charge without any troubles) and the discharging it to 0% to reset the coulomb counter.
Then I've charged it to 100% again and discharging it to about 60% because i've had to store the scope for several months.
But after 2 months, the IE NI2040 is now 0%, but the old original battery is perfect only1-2% loss.
When you use it after a full charge, it works perfectly, that's only when storing it that it discharges rather quickly.
Have a Nice Day.