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Comment by vmception | Hacker News Reader

The key points:

tests were averaging 55 mph

the battery pack has twice the capacity and is twice as dense, allowing it to fit in the same space as the stock battery, and delivers the same performance

so it is impressive and useful, not really much scifi here which is good, its just a double capacity battery in the same space that delivers the same performance

definitely has now reached the range I'm looking for. make it happen, and somebody please just make classic car shells have these batteries in them. I don't understand why its just tesla, a couple of other luxury car brands that cost twice or thrice as much for worse charging service, or luxury car brands that decided to make a fugly tron-esque version of their car instead of just doing the same thing they're known for with a battery under the hood. intentionally ignoring the cheaper vehicles because they're not in the running either.

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It's also much heavier and much more expensive. This really isn't a breakthrough more than it is a special case optimization. Any new design could easily have accommodated a similar capacity battery with traditional construction just by making the car 2cm taller or whatever.

I mean, lithium batteries are already pretty space-efficient. This kind of optimization surely has a home in some application (to be clear: it already does in consumer electronics!). I'm just not sure cars are where it's best applied.

does the weight impact anything consequential? I guess perhaps acceleration and handling? But I'm not sure the article went into that

I just want a car that does what is described, ideally without other tradeoffs. I would consider paying a premium for that, to an extent. I mean Tesla has been teasing Roadsters w/ 600 miles per charge at $250,000 for 5 years now. So someone just do the thing and make the option.

weight impacts everything; acceleration, handling, braking performance, brake wear , tire wear, road wear, generally increased NVH if the weight gain isn't part of the superstructure, drive train loads, consumable suspension (bushings/wear items) wear ..

the list goes on, but you get the point.

it's all a cost/benefit ratio between duration/range/cost/marketability/reliability ; you can take care of the technical issues behind weight gain, but is there still a market there once you do and the cost to produce skyrockets?

Is range consequential to you? The battery pack's already quite heavy (>1,200 lbs) and it takes both power and energy to move that much weight around. The bigger the pack, the more of both it takes to move it. The 100 kWh battery already gets 400 miles per charge. Doubling the battery pack with existing technology isn't going to get double the range. At some point there are diminishing returns where adding more batteries reduces the range due to the added weight.

Also keep in mind that with an electric car, most users will use a home charger and start each day at full charge (even the slow charger can manage this if you're getting enough sleep). At the article's state 55 mph to get their range, it would take just over 7 hours of driving to go 400 miles. That's plenty for daily, non-fleet use.

I don't want double, I want 20-25% more. That will cover all my edge cases.

> does the weight impact anything consequential?

Kinetic energy. That could make collisions more dangerous (though I’m not sure by how much)

Numbers:

Tesla Model S: 4600 lbs (Original battery: 1323 lbs) https://www.teslarati.com/tesla-model-s-weight/

Gemini Battery: additional 730 lbs https://www.carhp.com/news/one-s-prototype-battery-registers...

>1323 & 730 lb

Jeeez. That’s almost the curb weight of my Miata.

But, interestingly, miata's get pretty boring fuel economy given their size.

I'd call it downright bad if you're looking at earlier models.

Curious if they bothered to comply with the GVWR for the vehicle.

An extra 730lbs is most of the typical payload capacity for a typical car.

The model S has a GVWR of 5600lbs and weighs about 4600lbs meaning you can only put about 1000lbs of stuff in/on it safely.

With this extra battery weight there isn’t enough capacity left to carry more that two typical adults let alone any luggage.

It's almost like Tesla has to optimize for more than just raw battery performance.

Thx. I guess they were only interested in cars and not battery. Hence the article was rather poor. I was thinking where are you getting these data from as the article doesn't include much information. Some reply below showed added 700Lb to the car.

There is Opel Corsa-e, its brother Peugeot e-208, there is VW e-Golf, Renault Zoe (a bestseller). The problem is they are much too expensive for their segment. So manufacturers try to make those fancy cars, because the price is easier to swallow. It will change, but cars in general will get more expensive. Maybe within 10 years it will get to some sensible stabilization.

Are the safety parameters the same? Would it overheat more easily?

Tesla designed the entire chassis around the battery pack (as in, it's structural component). Traditional car companies are going to have to do a lot of very expensive retooling to something similar.

Traditional car companies moved to "platform" based vehicles 20 years ago and they refresh the entire platform every 5-ish years. This isn't really a big deal for any of them as evidenced by both Ford and GM already rolling out EV platforms.

"There's no way GM can build a sub-$100k mid engine Corvette" was a common refrain too. They didn't get to that size by being bad at designing cars.

They don't retool the factory every 5 years... I think you're underestimating things a bit.

Did ford integrate the battery pack into the chassis?

They're constantly retooling their factories. My dad worked at several GM factories for nearly 40 years. I feel like every year or two GM would announce a huge spend per factory to retool/upgrade/etc.

There are a lot of different things one can mean by that. that "structural pack" that elon has been talking about doesn't go live until the new Model Y chassis starts being built, which is maybe today?

The current level of tesla's battery/chassis integration is not any more sophisticated than everyone else that I can see.

>They don't retool the factory every 5 years... I think you're underestimating things a bit.

I think you don't know what you're talking about.

https://www.f150gen14.com/forum/threads/ford-prepares-to-ret...

>Did ford integrate the battery pack into the chassis?

Yes, they did integrate the battery pack into the chassis on both the mach-e and the lightning.

https://s3-prod.rubbernews.com/s3fs-public/styles/width_792/...

It took few years for traditional auto to learn that Tesla-style dedicated EV platform is the way to go, but they are doing it now. Their first EVs were ICE cars "converted" to electric (e.g. e-Golf) but VW now has their ID-platform, for example.

I'm curious how they cool it under heavy performance load. I'm assuming they're making a significant performance compromise to extend range by limiting discharge speed/heat production.

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