The figures seem a little off if they're going for realism.
EG:
Typical Drill battery as linked to in post is 63 WattHours (18V 3.5Ah) and a typical Heavy pack (2x NiMH D battery) would be around 15-30 WattHours (3V 5-10Ah) depending on manufacturer.
To get to KiloJoules just multiply that by 3.6 which would give you:
Medium (2x NiMH C battery) =27 - 54 charges
Heavy (2x NiMH D battery) = 54 -108 charges
Heavy+ - cordless drill = 226.8 charges
Now using a smartphone battery as an example of a light battery is interesting, because all smartphones use different battery tech to the other examples. They use lithium batteries which have a higher voltage per cell and generally have higher energy density so for example using a samsung S8 battery you'd have:
3.7V 3.0Ah = 11.1 Watthours 3.6 = 40 Charges.
Anyway I know you said you didn't want to get into that, I just wanted to add in some more or less correct numbers just in case.
The figures seem a little off if they're going for realism.
EG:
Typical Drill battery as linked to in post is 63 WattHours (18V 3.5Ah) and a typical Heavy pack (2x NiMH D battery) would be around 15-30 WattHours (3V 5-10Ah) depending on manufacturer.
To get to KiloJoules just multiply that by 3.6 which would give you:
Medium (2x NiMH C battery) =27 - 54 charges
Heavy (2x NiMH D battery) = 54 -108 charges
Heavy+ - cordless drill = 226.8 charges
Now using a smartphone battery as an example of a light battery is interesting, because all smartphones use different battery tech to the other examples. They use lithium batteries which have a higher voltage per cell and generally have higher energy density so for example using a samsung S8 battery you'd have:
3.7V 3.0Ah = 11.1 Watthours 3.6 = 40 Charges.
Anyway I know you said you didn't want to get into that, I just wanted to add in some more or less correct numbers just in case.
Edit//
Forgot to add in a typical watch battery such as :https://www.amazon.co.uk/Duracell-376-377-Watch-Battery/dp/B00E2QZ7HY
That would be about 0.018 WattHours, or 0.0648 Charges.