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Toyota bZ4X Usable Battery Capacity

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The bZ4X might have a 71.4 kWh battery, but in terms of usable power it's actually 64 kWh. This is from an article from a Norwegian EV new site.


Here are the changes that became known:
The battery capacity

The cars have a total battery capacity of 71.4 kWh gross. In the start-up phase, Toyota did not want to say anything about how much of this was applicable to the user, but they have been wise enough to change that. They now state that 64 kWh is the usable part of the battery capacity. The project manager for Toyota, Daisuke Ido, tells Elbil24 that they choose not to use the terminology "net capacity", as many others do, but "usable capacity". This doesn't make a big difference, so that's fine.

Percentage display
Among electric drivers, the instrument's display of range is often called a "guestometer". This is because the display of remaining kilometers is affected by many external factors, such as previous trips, the temperature during these trips and other things that may have changed since this was carried out. The experienced electric motorist is more interested in the percentage display, since this is an actual and concrete number that is real and reliable.
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While that doesn't seem too bad, real-world range is. 134 miles of real-world range (according to some publications) down from the 250 it was rated for is quite the drop.
All EV's have buffers on each end to lenghthen the life of the battery. I would rather charge this way than have lower range after a few years.
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Some of the buffers are mandatory. Some capacity is reserved at the top and bottom. It will not charge into that upper buffer and the car will shut down before the lower buffer.

In addition, there is a zero miles (km) remaining point on the Guess-O-Meter, which might be at the same point the car shuts down, or it might be well above that lower limit. Different cars (and different firmware versions) will implement any ”hobble” mode differently, at different points near the enforced lower limit of charge.

All of this makes direct comparison of different Guess-O-Meters like comparing apples and oranges.
Can anyone explain please if whatever miles are left after hitting 0 come from the usable battery capacity or from the buffer?
Can anyone explain please if whatever miles are left after hitting 0 come from the usable battery capacity or from the buffer?
Its a bit vague. the only confirmed value in interviews is "minimum of 8% SOC, but can be more. So at min 5.72 KW are reserved. And that is on top of a the buffer that manufacturers put to cover battery degradation. This is a Toyota specific buffer to "give the customer piece of mind" they can still find a charger even then driving to zero SOC. Which may be ok for petrol cars, but is an absolute no go for EVs. No one will drive their car down to zero and then be like ok i got 10-20 miles for find a charger. Its a completely wasted buffer.

But they also confirmed they will "release" this buffer for use in an upcoming SW update (summer time) a few more QOL changes coming in the same update
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