Swappable Fuel Cells ??

[Mike Watterson]

I read about Aluminium Air cells ages ago. Why are they rechargeable? Zinc Air are not and are similar chemistry. At the time I read it there was an issue about the Aluminium Oxide.  See what makes the dielectric in an electrolytic capacitor.

AFAIK it's a myth that car makers have ever blocked any kind of fuel or battery.

As I read it Mike, the fuel cell is replaced not recharged. Mention is made of a 90 second? minute? swap out time, akin to changing a gas bottle.
  Air to metal cells are not rechargeable but are recyclable.

I didn't think it could be rechargeable.

This isn't even fake news, it's wishful thinking.

[boater sam]

I read about Aluminium Air cells ages ago. Why are they rechargeable? Zinc Air are not and are similar chemistry. At the time I read it there was an issue about the Aluminium Oxide.  See what makes the dielectric in an electrolytic capacitor.

AFAIK it's a myth that car makers have ever blocked any kind of fuel or battery.

As I read it Mike, the fuel cell is replaced not recharged. Mention is made of a 90 second? minute? swap out time, akin to changing a gas bottle.
  Air to metal cells are not rechargeable but are recyclable.

I didn't think it could be rechargeable.

This isn't even fake news, it's wishful thinking.

If it proves to be true, it could make the Austin company more successful than it ever was making cars before. Any shares available?

[Mike Watterson]

The "Austin" company has no monopoly on this, nor the commercial or technical expertise. Put your money elsewhere, Sam.

Wikipedia isn't always accurate, but:
https://en.wikipedia.org/wiki/Aluminium%...ir_battery

The two big issues are that it's a primary cell, not rechargeable, so the economics are dubious and the Aluminium Oxide issue, which may inherently prevent the cell being viable. Viable electrode designs dramatically increase the cost and reduce the ability to recycle them. Without cheap complete recycling the cell is a disaster.

The technology has been in development for over 30 years and is unlikely to be viable. Why the obsession? The energy density.
Actually NiMH in volume are close to Lithium Ion in capacity (they weigh a lot more hence not used for cars) and may have longer life.
NiMH and LiIon may have 500 to 2000 cycles. Lead Acid more. I'm not sure about Nickel - Iron (used in Victorian era for electric cars).

Zinc Air cells used for everything from hearing aids to electric fences. They decay as soon as the air seal is opened. Aluminium Air cells have all the issues of Zinc (very similar) but harder to solve.

[Kalee20]

Petrol and diesel also have a lot of energy in a small volume. However, it's not energy density that's the real hazard, it's how it's contained in a stable and foolproof way. Although petrol burns rather well, we've found ways to handle it safely.

Petrol or diesel do indeed have a large energy density in practice, but unlike batteries, a can of petrol or diesel has no significant energy by itself.

A battery can self-destruct and go into meltdown (as has happened with lithium batteries). Whereas, a can of fuel can't do anything without an oxidiser (air).

A 2-compartment container, one side filled with diesel, the other side filled with liquid fluorine, now that might be a valid comparison!

[Refugee]

Petrol or diesel do indeed have a large energy density in practice, but unlike batteries, a can of petrol or diesel has no significant energy by itself.

A tank of fuel can be very dangerous in the event of mechanical damage just like sticking a knife through a lithium battery.
Once a tank of diesel becomes damaged the fuel gets exposed to air and will indeed burn.
Ignition will occur by contact with sparks or any other hot objects including friction between the object causing the damage to the fuel tank itself. This is why aircraft often turn into fire if they crash.

A damaged fuel tank on a moving vehicle will soon catch on fire if it has come loose and contacts the ground underneath.
An example of a friction ignited diesel tank.
https://www.independent.co.uk/news/train...24341.html

[BusyBee]

Petrol or diesel do indeed have a large energy density in practice, but unlike batteries, a can of petrol or diesel has no significant energy by itself.

A tank of fuel can be very dangerous in the event of mechanical damage just like sticking a knife through a lithium battery.
Once a tank of diesel becomes damaged the fuel gets exposed to air and will indeed burn.
Ignition will occur by contact with sparks or any other hot objects including friction between the object causing the damage to the fuel tank itself. This is why aircraft often turn into fire if they crash.

A damaged fuel tank on a moving vehicle will soon catch on fire if it has come loose and contacts the ground underneath.
An example of a friction ignited diesel tank.
https://www.independent.co.uk/news/train...24341.html

I see both sides on this but I think my main point would be that a tank of fuel is dormant without external influence but a Lithium battery can have an internal fault which initiates an explosion. Maybe in most cases the result of external effects not allowed for but I do remember from the past experience seeing fuel fires which were sorted quickly. Burning fuel in a tank will not usually spontaneously explode as there is absence of oxidiser to cause that (at least in a full tank) and a leak keeps the flame front away (I am presuming a bit here). Electric car batteries are usually in a fairly safe position but the effects of a physical rupture with a very high capacity battery? Liquid fuel will leak but does need to be ignited whereas a ruptured battery has capability of self ignition.

Tracy

[Refugee]

Lithium batteries need something to set them off.
The emergency cabin light batteries on some aircraft blow up however it usually happens on the ground when they are plugged into the ground generator. Hover boards are the same. These blow up because the charging circuit is poor.
Lithium batteries are very dangerous if they get hot due to misuse or bad charging. This is when they blow up.
The top will blow off a car battery if you disconnect the charger while it is still switched on due to the spark igniting the explosive mixture of gasses above the electrolyte.

[BusyBee]

The top will blow off a car battery if you disconnect the charger while it is still switched on due to the spark igniting the explosive mixture of gasses above the electrolyte.

That reminds me of how the chemistry teacher at school caught me out. He asked me to put a lighted spelter to a small plastic bottle in which he had collected hydrogen. I was cautious and I think the bang was greater when I finally lit it as the contents had had time to mix with more oxygen for a more explosive mixture

Tracy