After reading about submarines in World War II, I was curious about their battery capacity, specifically in comparison to modern Battery Electric Vehicles (ie Tesla, Bolt, Leaf, i3, etc).
I haven't been able to find a source that either answers the question in kWh or gives me enough information to calculate it myself.
My current guess is about 30 kWh, based on a figure of 12000 Ah in a 120 cell system, and a voltage of 2.75 V - 1.05 V
I would accept an answer for any class of submarine in WWII, but I was looking at the US Balao class.