ev battery swapping

[The Natural Philosopher]

It certainly did in the model electric world.

[The Natural Philosopher]

I am not convinced that is the mechanism for short lifespan

[Rod Speed]

Thats bullshit.

That's bullshit with nukes.

That's bullshit with nukes.

[Rod Speed]

It frys anyone anywhere near it.

[Paul]

It would be done with Ultracaps, which could charge slowly until the next car comes along.

An ultracap fits into the palm of your hand, and has a peak current output of 3000 amps. This is not a device you stick a screwdriver across :-) I don't think the substantial-looking tabs on the ultracap, can really handle 3000 amps. The thing would likely "get warm". These are the kinds of things they experiment with on electric drag racers.

"A student team from Brigham Young University (BYU) set a new record for the world's fastest electric drag racecar. The team modified a production EV1 donated to the university by the General Motors Corporation and installed a bank of 160 UltraCapacitors rated at 2700 farads each."

Rather than a technology issue (the "power pyramid"), it's a cost issue. What would it cost to build a "petrol station" with infinite peak output ? It would cost a f****ng fortune, that's what it would cost.

It would be as expensive as running your "petrol station" using these as buffers. One of those might cost a couple million. Now, imagine if there was yet another trailer filled to the scuppers with ultracaps. But these are the items that allow you to run a petrol station with a "7kW feed" :-) Buffer trailers. That way, the grid only provides the "average power vended", rather than being asked to provide the peak desired rate, with a very expensive transformer.

I'm convinced that some day, the long charge time issue will be solved. And hopefully, before too many BEVs have been minted with the existing tech. The aluminium battery still doesn't have the charge cycle count solved. But the existence of a prototype, is a start.

Paul

[alan_m]

There is a big difference between something that can do a quarter of mile quickly for a few seconds and a road car required to do perhaps

200+miles on a single charge.

Dragsters can use 6 gallons of Nitromethane in around 4 seconds - around

24 gallons per mile, and not 24 miles per gallon

The biggest weight/size trailer normally allowed on the UK roads and "the trailer has enough juice for 30 recharges in total before it needs some charging attention"......."that under favourable conditions, a trailer can be fully charged and ready to rock in just four hours"

[Andrew]

You forgot the fuel duty and 20% VAT compared to 5% using electric.

[Tim Streater]

What has this to do with *electric* drag racecars ?

[SteveW]

A bit of an underestimate I think. Back in the '90s friends and I started a website about drag racing and interviewed some of the teams. IIRC the Showtime funny car of the time had a 8.5l V8, kicking out 6,400 BHP and using 13 gallons of Nitromethane for the 1/4 mile!

We didn't keep the website running, as after we'd organised a demonstration for Santa Pod raceway, they had their own built :(

[alan_m]

Did that include the burnout and staging?

[Theo]

200,000 miles would be a more plausible figure.

50kWh does 200 miles on a charge (2021 MG5 estate EV: 'combined' 210miles, 52.5kWh battery, 48.8kWh usable, launch price £26K)

EVs get 3-4kWh/mile, so that would be £16.50-22, or 8.5-11p/mile.

3.75p/mile battery depreciation, total 12.25 - 14.75p/mile.

Or not, with the above figures.

Don't forget you can often get cheaper tariffs to cheap using night time electricity, or from solar panels (if the vehicle is at home during the day, or parked somewhere with panels, etc).

Theo

[The Natural Philosopher]

Or if you run a really economical car and get 60mpg instead of my 35, diesel MUCH cheaper

If you ignore the depreciation on the solar panels

[alan_m]

Surely all green renewable energy is free?

[alan_m]

Just making the point that something designed for the drag track is not necessary what is required for the car you buy for the public highway.

[alan_m]

But at that time the battery may be less than 75% of its original capacity - assuming not too many fast charges and no abuse of the battery.

I'd be more inclined to believe what one manufacturer gives for the real world

Start off with 245 miles @ 31mph at an ambient temperature of 20C Change the speed or temperature (on the web page above) and you get more like 145 miles @ 68 mph and less if the ambient temperature drops.

The reviews of the MG5 EV suggest from £30,000+ and to get anywhere near to the headline range the most ECO mode has to be selected which possibly doesn't make it the most comfortable for long journeys.

The price rise of 80% has just been announced. I'm not sure that there any more cheap night time tariff will be left in the market place soon. With so many EV charging at night there will not be any spare capacity.

Do you believe that a commercial solar panel charging station is going to be cheaper than grid mains? If you have solar on your own roof then maybe fuelling your EV may be cheaper during the summer months.

[Paul]

You've heard of the idea of scaling, right ?

The dragster only has room for a small number of capacitors.

In a *stationary* application, you can make the installation a lot larger.

I'm not designing the thing for you, merely pointing out there are technologies with the capability to blast things to kingdom come. If you needed to charge a car in twenty seconds, I bet a physicist could design something for you. You don't need a transformer the size of the Queen Mary, but you do need some sort of device which can store charge and release it faster than Lithium. Lithium fastest 100% to 0% discharge recommended rate, is around three hours (like on a Powerwall).

If you wanted to drive a load for 20 seconds, the Li bank would have 3 hours capacity for the job, and could charge

540 cars before needing a recharge. If the resulting bank is too big to be realizable, because the discharge capability is so low, that's where an ultracap could change things. But even an ultracap can overheat. Or blow for that matter.

The beauty of the Aluminium device, is it's cheaper than Lithium and smaller than Lithium. And perhaps it makes sense to abuse it like this (as a two-stage battery bank inside a car). At the BEV petrol station, since that is a stationary application, you can trade size for lifespan, and use a tech which does not wear out while charging cars. An ultracap might be good for a million cycles under some set of conditions (not on the dragster).

Paul

[Tim+]

Following the price hike in my night time rate, I’m getting near to 2p per mile in “fuel” cost. Just terrible.

Tim

[SteveW]

Good question, I don't think so, but I can't remember for sure. However, burnout would be the only candidate for serious fuel usage, while staging at idle would be using very little. Even burnout is only using a fraction of the power - you can't even see the movement of the butterflies. So worst case, it would increase the consumption, but be unlikely to double it.

[The Natural Philosopher]

You missed the /sarc

[Pomegranate Bastard]

It's batteries, you thick git.

It's batteries, you thick git.

It's batteries, you thick git.

It's batteries, you thick git.