Does V2G damage the battery?

It adds energy throughput, typically a fraction of what driving adds, at low power. Fast charging above 100 kW was linked to faster ageing in a large study.

Explained in

Bidirectional charging · Stop 05What does it mean for the battery?Extra energy through the battery, computed for one household, and what is known about ageing, data access and the limits owners can set.

Batteries age with time and with use. In a large telematics study, frequent fast charging above 100 kW went with faster capacity loss, up to 3.0% a year, while mostly AC or lower-power charging went with about 1.5%. Powering a house is low-power use, closer to AC charging than to fast charging. How cells age in general is explained in eMobility and EV basics, stop 08.

From “What drives ageing”, stop 05
  1. What is bidirectional charging?Smart charging in which electricity can also flow from the car's battery back to the charging point, to a device, a house or the grid.
  2. What is the difference between V2H and V2G?V2H powers the house behind its meter; V2G feeds the public grid. V2G brings in generator rules, metering in both directions and the electricity market.
  1. Geotab: Updated analysis finds average battery degradation of 2.3% per year, with charging behaviour emerging as a key driver, 13 January 2026. https://www.geotab.com/uk/press-release/ev-battery-health-degradation-fast-charging-study/. Checked 09 Oct 2026.