Why VW Recommends Using the VW eGolf Battery Sparingly When It Comes to Fast-Charging
VW's statement about DCFC reads: “Requires charging at select DC fast-charging stations. Frequent and consecutive high-voltage charging (including DC charging) can permanently decrease the capacity of the high-voltage battery. See your Owner’s Manual for details." There really isn't much more than that in the big manual. And the warranty doesn't apply if the owners manual is not followed.
Ronald B. Vlack explains in a VW e-Golf group on Facebook.
"The e-Golf battery has no cooling system like Tesla, i3 etc. Only passive cooling to save cost and weight. High speed charging generates lots of heat and heat is the enemy of BEV batteries. That's probably why VW recommends using sparingly and not consecutively. When they announced the change to no cooling, they said their tests showed it wasn't needed, but didn't indicate if the tests included some mix of high speed charging.
"The battery warranty does say it doesn't apply if guidelines described in the users manual are not followed. These guidelines are pretty specific, so assuming VW logs battery/charge/temp data, they do have an out on 8 year 70% coverage," Vlack explains.