Battery capacity, range and efficiency

[philip42h]

Which numbers do you believe and base your journey planning on?

I've been happily doing lots of short journeys (<5 miles) and the trip statistics have been returning around 2 miles / kWh - and that's fair enough because the heating has been on for pretty much the whole journey each way. I simply plug in the granny charger every few days to top the Battery up overnight. 👍

Next month we intend to visit family up north and down south - well out of the range of a single charge - so I'm looking to plan the necessary recharging stops. And, because I have no experience as yet, took the car out yesterday on a mostly motorway 'range calibration and charging test':

• I left home with a 92% charge and an estimated range of 225 miles on the GOM.
• 95.7 miles later, I reached my recharging stop (Gridserve rapid) with a 36% charge and an estimated range of 91 miles on the GOM for an average trip efficiency of 3.0 miles / kWh.
• It was cold (5 - 9 degrees), I had the aircon on Auto + Eco and drove at the speed limit where I could.

So, I used 134 miles of range (225 - 91) to cover just 95.7 miles - not entirely surprising since the GOM has no real history to work with and it's just an estimate anyway.

It suggests that I covered those 95.7 miles at 3.0 miles / kWh and, thus, used 31.9 kWh in doing so.

I used 56% of the Battery (92% - 36%) to deliver those 31.9 kWh. This implies that the useable Battery capacity is ~ 57kWh - which is at odds with the generally accepted useable capacity of 64 kWh. If we believe that the useable capacity of the battery is 64 kWh, then the 56% used would equate to 35.8 kWh and an efficiency of around 2.7 miles / kWh.

Either way, that would give me an effective range of around 170 miles under these specific test conditions. And which corresponds very well with the figures from the Toyota bZ4X range calculator if I assume that the journey was 100% motorway.

So, what numbers do you base your journey planning on?