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BMW EV achieves 1000km in range using Dual-Chemistry batteries

forbes.com

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Re: BMW EV achieves 1000km in range using Dual-Chemistry batteries

#31

Post by wongarsu »

keenmaster wrote: post #23
wongarsu wrote: post #17

Earlier quoted context omitted.

Yes, to get more range you need more batteries, and those increase your weight meaning you need more batteries. But those increase your weight, so you need even more batteries. The tyranny of the rocket equation. Not really specific to this dual-chemistry though, the same holds true for normal EVs and for gasoline-powered cars.

True, but the difference here is that the second battery isn’t even used most of the time, and if it was it would die quickly.

But is that really substantially different from somebody keeping their gas tank always at least half full, or making normal short-range trips with the long-range version of a Tesla?

Everyone already tried selling EVs with smaller batteries. The might be more efficient on paper but they don't sell. Turns out that trips people take once in a blue moon are still important to them, so a battery tuned to making that possible once in a blue moon sounds very useful.

Re: BMW EV achieves 1000km in range using Dual-Chemistry batteries

#33

Post by 0_____0 »

numpad0 wrote: post #32

How did they manage to mix powers from two batteries? The voltages to the bus bar usually has to be kept close for a battery pack to work, usually.

TFA

>The Gemini pack also includes a proprietary battery management system and DC-DC converter to enable the NMC cells to replenish the LFP cells as they get depleted.

Re: BMW EV achieves 1000km in range using Dual-Chemistry batteries

#34

Post by adrianN »

_ea1k wrote: post #24
wongarsu wrote: post #17

Earlier quoted context omitted.

Yes, to get more range you need more batteries, and those increase your weight meaning you need more batteries. But those increase your weight, so you need even more batteries. The tyranny of the rocket equation. Not really specific to this dual-chemistry though, the same holds true for normal EVs and for gasoline-powered cars.

It is a bit different from the rocket equation. The impact of weight on energy consumed per mile in a car is not particularly large. You can add hundreds of pounds and the impact will be negligible.

At least if you have regenerative brakes. Otherwise weight matters in stop and go traffic quite a bit.

Re: BMW EV achieves 1000km in range using Dual-Chemistry batteries

#35

Post by RcouF1uZ4gsC »

wongarsu wrote: post #31
keenmaster wrote: post #23

Earlier quoted context omitted.

True, but the difference here is that the second battery isn’t even used most of the time, and if it was it would die quickly.

But is that really substantially different from somebody keeping their gas tank always at least half full, or making normal short-range trips with the long-range version of a Tesla? Everyone already tried selling EVs with smaller batteries. The might be more efficient on paper but they don't sell. Turns out that trips people take once in a blue moon are still important to them, so a battery tuned to making that possi…

> But is that really substantially different from somebody keeping their gas tank always at least half full, or making normal short-range trips with the long-range version of a Tesla?

A gallon of gas weighs around 6 pounds. A car usually has less than 20 gallon capacity. Keeping it half full would mean you keep 10 gallons which is 60 pounds. Even if you kept it full all the time, it is 120 pounds. That is going to be a lot less than any sizable battery ( theTesla Model 3 battery weighs around 1000 pounds).

Re: BMW EV achieves 1000km in range using Dual-Chemistry batteries

#36

Post by fragmede »

adam_arthur wrote: post #28
keenmaster wrote: post #27

Earlier quoted context omitted.

“Far better driving dynamics than gas cars”? No way. Go throw a BMW 3-series around some corners and compare to the Model 3 - you will feel the weight of the batteries. I would have said compare to a Porsche but that’s a different price range. Note: I’m a big fan of EVs. I’m just saying that handling is one of their weaknesses until battery density gets a lot better.

The average people don't buy BMW or Tesla, they buy Honda CR-V. And they'll appreciate 500mi range far more than being able to take turns fast

Zero people drive 500 miles in a straight line on a daily basis though, so cornering ability is more important than 500 miles of range, especially when most gasoline cars (several diesels do) don't get that much range in a single tank. The biggest change for EVs is the ability to charge the car at home, though, so you wake up every morning with a full tank of "gas". An EV with only 50 miles of range would do great for most people if they had home charging given how many miles "most people" drive in a day.

I don't work for BMW (or Honda, or Tesla) though, so what do I know.

Re: BMW EV achieves 1000km in range using Dual-Chemistry batteries

#38

Post by MostlyStable »

TheLoafOfBread wrote: post #30
Gravityloss wrote: post #20

Earlier quoted context omitted.

https://electrek.co/2023/07/11/europe-passes-two-big-laws-to... > the new rules also mandate simpler charger payments. As-is, some networks require subscriptions or app downloads. But under these rules, customers must be able to pay with cards or contactless devices, and prices must be displayed to the customer.

Five years late.

I completely agree that chargers need to have simple payment methods, but doesn't the largest public network (Electrify America) already work this way? Yes they have an app, and you can get cheaper prices if you pay their subscription, but you don't need to use it. You can just pay with no account using the card swiper on every charge point, I'm pretty sure.

Re: BMW EV achieves 1000km in range using Dual-Chemistry batteries

#39

Post by MostlyStable »

I watched a youtube video on this recently, and I believe that they never mentioned battery lifetime in it. This article said that one of the chemistries only lasts a few hundred cycles, but, because of the use pattern of the dual chemistry is "expected to last the lifetime of the vehicle".

I really hope this turns out well, but given the current lack of specificity, I'm going to guess that overall pack longevity is going to be the Achilles heel of this battery.

Always happy to see people trying innovative new ideas though. Most of them won't work, but we can only find the ones that do if someone tries it. Hope this one turns out better than I fear.

Re: BMW EV achieves 1000km in range using Dual-Chemistry batteries

#40

Post by instagib »

natch wrote: post #8

BMW, build a charging network. That’s really the most consequential thing for drivers.

Building it is not enough. Need incentive to maintain the network.

Next, make the vehicles cheap enough by some means that we adopt electric vehicles faster.

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