Net Battery capacity decrease for 07/23 model (81,1 to 76,6 kwh)

Took me a while to find this info on the French BMW site but you are correct about the 'net' figure, although the eDrive35 still shows the 'old' figures. The UK site still shows the previous figures.

Note that the total battery capacity is unchanged so I don't think there is any change in the battery. The WLTP range is the same as it was. BMW are typically unhelpful in not specifying what 'net' means. We have always taken this as the usable battery, with the difference to 'gross' being the built in buffer. Maybe they have increased the buffer (but that would reduce the WLTP range), maybe they have changed the definition of 'net', maybe it is just a mistake.

Is there a BMW helpline in France you can contact to see if they can explain it?

J_P said:

Took me a while to find this info on the French BMW site but you are correct about the 'net' figure, although the eDrive35 still shows the 'old' figures. The UK site still shows the previous figures.

Note that the total battery capacity is unchanged so I don't think there is any change in the battery. The WLTP range is the same as it was. BMW are typically unhelpful in not specifying what 'net' means. We have always taken this as the usable battery, with the difference to 'gross' being the built in buffer. Maybe they have increased the buffer (but that would reduce the WLTP range), maybe they have changed the definition of 'net', maybe it is just a mistake.

Is there a BMW helpline in France you can contact to see if they can explain it?

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Says the same thing on the Swedish site for both eDrive 40 and M50, it could be a new battery supplier where they need a higher buffer to be able to have the same specs for 10-80% charging time and such. Or that the chemistry isn’t as stable and will degrade more and they don’t want that degradation to be visible.

The i5 showing the old i4 net figures somewhat suggests that it’s not the same battery as before in the i4 that they just want more safety margins in. Unless they are trying to up sell the i5 by nerfing the i4 of course.

For whatever reason it would be a nerf to future i4s to have less net capacity.

BMWdav said:

Says the same thing on the Swedish site for both eDrive 40 and M50, it could be a new battery supplier where they need a higher buffer to be able to have the same specs for 10-80% charging time and such. Or that the chemistry isn’t as stable and will degrade more and they don’t want that degradation to be visible.

The i5 showing the old i4 net figures somewhat suggests that it’s not the same battery as before in the i4 that they just want more safety margins in. Unless they are trying to up sell the i5 by nerfing the i4 of course.

For whatever reason it would be a nerf to future i4s to have less net capacity.

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The chemistry of the battery pack is the right track, knowing that in the i5, the data is almost the same as the i4 before 07/23. In addition they updated the consumption data with the release of the i4 x40. I think the real autonomy of the new i4 will be lower than the current version. To monitor.

Vassilis said:

However if you visit ev-database, you will see that the figures changed there too in respect of range. It used to be 475km and now the range is 515km. I really don' t know what happened. I do speak for the eDrive 40

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I think that BMW, following software optimizations since the release of the car, has updated the WLTP values, to avoid negative customer feedback following the drop in net capacity, BMW has not published the i4 update with the old battery. I therefore suspect that the i4 produced after July 2023 will have a range of 4 to 5% less than those before July 2023 ....

i4 M50 France said:

I think that BMW, following software optimizations since the release of the car, has updated the WLTP values, to avoid negative customer feedback following the drop in net capacity, BMW has not published the i4 update with the old battery. I therefore suspect that the i4 produced after July 2023 will have a range of 4 to 5% less than those before July 2023 ....

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But this doesn' t explain the increase in range that ev-database shows. On the contrary it should actually show a decrease in range.

I did see through another link that the part numbers for a replacement battery changed in 2023. The link showed the replacement cost at about $30,000! but there were two part numbers depending on whether the car was 2022 or 2023. Unfortunately I have no idea where that link is now.

Anyone notice the AC charge time of half the i4 (4 vs 8 hours)? Yet the AC charge rate is 11 kWh for both. I wouldn’t trust these numbers just yet.

Lone stranger said:

Anyone notice the AC charge time of half the i4 (4 vs 8 hours)? Yet the AC charge rate is 11 kWh for both. I wouldn’t trust these numbers just yet.

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It's for the i5 with 3 phase maybe.

Lone stranger said:

Anyone notice the AC charge time of half the i4 (4 vs 8 hours)? Yet the AC charge rate is 11 kWh for both. I wouldn’t trust these numbers just yet.

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In Greece there are still 8,25Hrs

One thing about the range:
I'm pretty sure that BMW can just change the number for the net battery capacity, but they cannot change the number for WLTP without recertifying the range itself with the usual testing methods. So it would in theory be possible that the data sheets show the old WLTP numbers but the new battery numbers and range will actually change in the future.

But: I don't think they would be doing that, as it would be a really bad thing and give lots of room for legal actions against BMW. Also I don't think many people would just accept paying the same (or higher) price for a car with now around 6% less net capacity. In my opinion they may have just changed it to reflect the actual capacity or something.

P.S. If my car would actually come with less net capacity, I would probably not accept that. Imagine buying a car with almost 570km of range and getting one with 535km of range, just to make their new model more attractive.

I suspect this is more an issue of errors in updates or corrections based on new software than real changes in battery capacity.

Maybe it just reflects the safety margin better.

i4 M50 France said:

It's for the i5 with 3 phase maybe.

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optional 22 kW AC charger for the i5

2 possibilities:
- BMW has detected a weakness in the battery pack and has decided to increase the buffer. this leads to a loss of autonomy of approximately 5%. i4s produced after July 2023 will have less battery life than those before July.

- Change of prismatic battery or chemistry supplier. it may need more buffer than the current one.

in any case, it is certain that the new i4s will have 5% less autonomy.

happy to receive my car in June.

J_P said:

I did see through another link that the part numbers for a replacement battery changed in 2023. The link showed the replacement cost at about $30,000! but there were two part numbers depending on whether the car was 2022 or 2023. Unfortunately I have no idea where that link is now.

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