1000 Wh/kg would be roughly 2X the best currently on the market, so that would be amazing if true.

More like 4x. Where can you get anything past about 250 Wh/kg?

Lithium-Sulfur:

https://oxisenergy.com/products/

The catch here is that they don't last that many cycles and the figure per unit volume is not amazing.

Great for aircraft though.

That page says they're only hoping for availability soon.

I've been following this company for years. They used to be overly optimistic, but got a reality check along the way and now are more careful in their statements.

Anyway 400Wh/kg are available as samples - that's not far away from 500Wh/kg.

Makes me wonder if this came to pass. Could an electric car be too light? Is there a minimum weight a car needs to be?

If the battery got small and you don’t have the ice, could it be a problem? Would they add weights?

An ice is actually pretty light in some cars. Aluminum blocks save a lot of weight. In economy cars you can lift both out by hand (I wouldn't recommend it, the angles are not really what your body handle well but a normal human can do it)

Most of the weight in a car is the frame which is a lot heavier today than similar cars of 30 years ago to pass modern safety standards.

Even if there is too little weight it is best for the required components to be as light as possible. The ability to add weight where you need it for handling reasons verses where the drive train forces it to be is often important.

> Most of the weight in a car is the frame which is a lot heavier today than similar cars of 30 years ago to pass modern safety standards.

Yes, this is what I was saying to people that a lot of crash worthiness demands now are counterproductive when everybody now drives 1.5, 2.0t bricks on wheels because of that.

Yes, that allowed for few more percents survivability in head on collisions, but at the huge expense of everything else.

Being able to shave off 200kg off an average vehicle will save way more lives than the amount of lives those 200kg save during 60km/h+ head on collisions.

For sure! F = μN, so if the weight of the vehicle is too low there will be very little friction force keeping the tires from losing traction while breaking accelerating and turning. Practically speaking, it's common to load your pick-up truck with sand bags in snowy environments in order to increase the amount of weight on the back tires since some models of pick-ups don't have much weight in the back half. Personally, I have fishtailed off the road when there was nothing in the truck bed in icy weather.

Indeed F = μN, but also F = ma, so you don't need as much F to accelerate a lighter vehicle (that is, one with lower m).

What you're describing about your pickup is the balance of weight, not the total weight.

You are forgetting forces to overcome effects which are independent of mass. For example, you might find that your car is blown off the road by a light breeze.

Hah, yeah, an earlier version of my post said something about external/edge effects as you approach 0 mass, but I didn't think it was germane to my main point.

> For example, you might find that your car is blown off the road by a light breeze.

We should be so lucky! An EV as light as a bike...

I wonder where the danger point really is. I've driven some lighter, smaller cars that were borderline dangerous in a stiff crosswind.

Your comment reminds me of a FAQ I read years and years ago when the internet was first starting.

It was for a male enhancement product, and one of the questions was basically how large should I let this thing get? :)

What as the answer?

Just add more battery, nothing wrong with having more range.