Battery Life Span

This depends significantly on how the battery is maintained. Under healthy conditions, the battery is rated for 800-1000 cycles. This can be reduced depending on use and storage/care of your battery. Additionally, regarding charging batteries, they can be charged on or off the bike and has its own LCD gauge for charge levels.

Keep your battery charge level between 30-80% as much as possible. This will significantly increase the lifetime use of your battery cells. Don't store your battery plugged into the charger. Charging should be monitored, and batteries should not be left plugged into a charger.

CHARGING

• The red LED lights on: The battery is being charge (Figure A)
• The red LED light becomes green: The battery is fully charged and you can unplug the charger. (Figure B)

Further Reading:

Charging: Charging Lithium-Ion

Lifespan: How to Prolong Lithium-based Batteries

Note - Never dispose of L-ion batteries in household garbage or recycling. 

Learn more here: Used Lithium-Ion Batteries | US EPA