SDS100/SDS200: SDS100 large Battery charging

[Saint]

I have had my sds100 scanner since Sept. 2019 and notice that when charging the large battery this is what I see now.
When I have the scanner charging from my usb port on the computer it will only charge to 4.17v and the green light is on and says it's charged, then I unplug the scanner from the usb port and it goes down to 4.05v

plug it back in and it goes to 4.17v

When I charge it by plugging it into the wall socket it will charge to 4.21v, When I first got the scanner it would also charge to 4.21v in the wall socket
But when I unplug the scanner from the wall when it's fully charged 4.21v it goes down to 4.10.
Is this normal or is this battery starting to deteriorate even before it's a year old
Steve

 

[flippus1]

The maximum charge also depends on how much power the supply puts out. The computer probably puts out less than the wall charger. Make sure the charger can put out 2 amps. 3 amp supply may give you more on top end. It’s always gonna drop slightly after unplugging. Buy extra battery and charger combo. Nice having extra battery pack

 

[dazza0768]

Yes normal

 

[Saint]

The maximum charge also depends on how much power the supply puts out. The computer probably puts out less than the wall charger. Make sure the charger can put out 2 amps. 3 amp supply may give you more on top end. It’s always gonna drop slightly after unplugging. Buy extra battery and charger combo. Nice having extra battery pack

Thanks for all the information, I also have an extra battery and charger so i'm good to go, nice to know there is nothing wrong with charging or the battery.
Steve

 

[dazza0768]

Batteries need more power than what they hold to charge otherwise they will stay at a certain voltage without charging. Mine is brand new and does exactly what you are saying.
USB voltage is higher than battery.