The EV fact thread

[BTB 500]

Pretty sure they require recertification every three years. How they are tested for that I don't know but having been involved in NDT none of it is easy or cheap.

AFAIK Toyota's tanks (for example) are certified for 15 years - the expiration date is on the inside of the filler flap ("do not refuel after ..."). I assume they'd need to be re-certified at that point.



The tanks are constructed in 3 layers, the innermost of which is an inert plastic:

 

[Bellow]

AFAIK Toyota's tanks (for example) are certified for 15 years - the expiration date is on the inside of the filler flap ("do not refuel after ...").

Fair enough - though I'm sure I saw 3 years as a timescale for some form of retest.

I assume they'd need to be re-certified at that point.

A quick look around the 'net suggests the car will be scrapped rather than the tank recertified.

View attachment 166201

The tanks are constructed in 3 layers, the innermost of which is an inert plastic:

It is degradation of the innermost layer that limits the tank's life as the very small hydrogen molecules can escape when that happens. This is similar to CNG tanks' construction and periodic recertification is the norm for them - at least in the USA. Those tanks though are usually retrofits to vehicles and therefor easily removable for testing - not embedded in the vehicle as with a fuel cell car. Pressure testing is done within purpose-built concrete chambers to contain any failure. Testing with the tank in the car is extremely unlikely. To give an idea of what's at stake here, I have known of fatalities when blanking plugs on vessels failed. In one instance, a brass - where it should have been steel - plug blew, ricocheted off a steel beam in the roof of the chamber and hit and killed a guy outside it. If, that plug's area exposed to pressure was say 1 square inch and the pressure was 700bar, the force on it was 4.6 tons.
Thing is though, with the high cost of a fuel cell, writing off a car at 15 years old because the tank cannot be recertified or replaced economically is a bigger financial hit that writing off any other vehicle at the same age. In California apparently there is a high disposal cost of tanks such as these. Whether the cost can be covered by salvaging the precious metals in the FC is unknown to me.

View attachment 166200

 

[Will]

I wonder if these tanks would be affected following an accident - certainly they should be designed to withstand some forces but would they need testing etc afterwards.

You can imagine the news stories if these were in use in enough numbers and one exploded or something! I wonder if they would be allowed in the channel tunnel? They don’t like LPG vehicles.

Not sure they’re likely to catch on anytime soon though so probably a moot point in reality.

Seen plenty of conventional diesel buses broken down over the years of course. I’m guessing the driver of said bus in the news story above didn’t notice level of charge dropping and continued as normal. Like those who seem to run out of fuel I guess it can happen

 

[Bellow]

I wonder if these tanks would be affected following an accident - certainly they should be designed to withstand some forces but would they need testing etc afterwards.

In cars they are embedded within the car for accident protection and I guess if the tank sustained damage the car's occupants would already be dead.
JCB though are mounting theirs on the roof of vehicles. Not like a digger never tumbled down a hill or had something dropped from a crane on it...

 

[BTB 500]

A quick look around the 'net suggests the car will be scrapped rather than the tank recertified.

That sounds pretty unlikely - do you have a source?

It is degradation of the innermost layer that limits the tank's life as the very small hydrogen molecules can escape when that happens. This is similar to CNG tanks' construction and periodic recertification is the norm for them - at least in the USA. Those tanks though are usually retrofits to vehicles and therefor easily removable for testing - not embedded in the vehicle as with a fuel cell car.

Why do you say the tanks are 'embedded'? On larger fuel cell vehicles (buses certainly) having them on the roof is common ... access couldn't be much easier than that:



The Toyota Mirai has them under the floorpan, easily accessible from under the vehicle.

And I thought testing/certification was to do with risk of rupture, rather than tiny amounts of gas seeping out?

Pressure testing is done within purpose-built concrete chambers to contain any failure. Testing with the tank in the car is extremely unlikely

Again this seems to be about risk of rupture rather than leakage. Silly question, but why on earth would testing like this be done with gas at high pressure rather than hydrostatically (which is virtually risk free)? Diving cylinders are routinely tested to 500 bar - this is relatively cheap and easy.

Thing is though, with the high cost of a fuel cell, writing off a car at 15 years old because the tank cannot be recertified or replaced economically is a bigger financial hit that writing off any other vehicle at the same age.

Again please give your source for stating vehicles would be written off rather than simply re-tested (or having a new cylinder fitted - surely cheaper than putting a new battery pack in a BEV).

In California apparently there is a high disposal cost of tanks such as these.

That makes no sense - source? They are relatively small and light and (as above) constructed of plastic/carbon/fibreglass rather than anything hazardous. The number requiring disposal so far must be tiny.

 

[BTB 500]

I wonder if these tanks would be affected following an accident - certainly they should be designed to withstand some forces but would they need testing etc afterwards.

You can imagine the news stories if these were in use in enough numbers and one exploded or something!

The USA has been one of the biggest markets for the Mirai ... given their liability laws there's no way a major manufacturer would launch a product there if there were any potential question marks about safety. Toyota say that the Mirai's gas tanks were even shot at as part of their testing:

Toyota Mirai: the safety facts

See how Toyota has engineered safety into the Toyota Mirai and why the hydrogen that powers it is safe.

mag.toyota.co.uk

IIRC they have sold about 25,000 Mirais - a tiny volume by automotive standards, but they've been on the road for 10 years now without (AFAIK) a single incident. And hydrogen buses have been in smaller scale use for decades.

I wonder if they would be allowed in the channel tunnel? They don’t like LPG vehicles.

AFAIK they have a blanket ban on anything powered by flammable gas, which would include hydrogen.

I’m guessing the driver of said bus in the news story above didn’t notice level of charge dropping and continued as normal. Like those who seem to run out of fuel I guess it can happen

I think there's a specific problem with buses due to the interior volume that needs continuously heating (with the doors opening regularly). It's not just the normal cold weather battery degradation.

 

[BTB 500]

JCB though are mounting theirs on the roof of vehicles. Not like a digger never tumbled down a hill or had something dropped from a crane on it...

I suspect JCB have given that some consideration.

Their tanks are Kevlar lined and designed to release gas in the worst case, rather than going 'pop'. Hydrogen is much lighter than air and disperses very quickly in the open.

The 1937 Hindenburg fire is probably the best known hydrogen disaster, with a gigantic volume (200,000 cubic metres) of gas being ignited. But actually the large majority of people inside at the time survived.

 

[Bellow]

That sounds pretty unlikely - do you have a source?

An anecdotal comment on the 'net - nothing more. But, given the talk of EVs being scrapped if a battery fails and 10-15 year old diesels are scrapped over things like head gasket failure or subframe corrosion it isn't that outlandish a claim.

Why do you say the tanks are 'embedded'? On larger fuel cell vehicles (buses certainly) having them on the roof is common ... access couldn't be much easier than that:

Fine for a bus maybe but a Mirai tank weighs 95kg and high up on the roof isn't the place for that in a car. NB. craneage required for handling on-roof tanks - something conspicuously absent in automotive workshops.

The Toyota Mirai has them under the floorpan, easily accessible from under the vehicle.

'Easily' is stretching it a bit but no worse than an EV's battery.

And I thought testing/certification was to do with risk of rupture, rather than tiny amounts of gas seeping out?

Both it would seem.

Again this seems to be about risk of rupture rather than leakage. Silly question, but why on earth would testing like this be done with gas at high pressure rather than hydrostatically (which is virtually risk free)? Diving cylinders are routinely tested to 500 bar - this is relatively cheap and easy.

It wouldn't. Pressure testing is always with fluid.

Again please give your source for stating vehicles would be written off rather than simply re-tested (or having a new cylinder fitted - surely cheaper than putting a new battery pack in a BEV).

An anecdotal comment on the 'net as per earlier. We don't know the costs of a new tank (be sure though, 95kg of carbonfibre construction will not be cheap) or testing.

That makes no sense - source? They are relatively small and light and (as above) constructed of plastic/carbon/fibreglass rather than anything hazardous. The number requiring disposal so far must be tiny.

Presumably, it involves complete disposal and, reflects that as the tank sits in the vehicle it will still be pressurised and not necessarily that easy to empty (car no longer 'running'). My local breaker yard has umpteen LPG tanks still with considerable quantities of LPG within from vehicles scrapped. There's no easy way to dispose of the contents.

 

[BTB 500]

An anecdotal comment on the 'net - nothing more. But, given the talk of EVs being scrapped if a battery fails and 10-15 year old diesels are scrapped over things like head gasket failure or subframe corrosion it isn't that outlandish a claim.

Fine for a bus maybe but a Mirai tank weighs 95kg and high up on the roof isn't the place for that in a car. NB. craneage required for handling on-roof tanks - something conspicuously absent in automotive workshops.

'Easily' is stretching it a bit but no worse than an EV's battery.

Both it would seem.

It wouldn't. Pressure testing is always with fluid.

An anecdotal comment on the 'net as per earlier. We don't know the costs of a new tank (be sure though, 95kg of carbonfibre construction will not be cheap) or testing.

Presumably, it involves complete disposal and, reflects that as the tank sits in the vehicle it will still be pressurised and not necessarily that easy to empty (car no longer 'running'). My local breaker yard has umpteen LPG tanks still with considerable quantities of LPG within from vehicles scrapped. There's no easy way to dispose of the contents.

Ok so only speculation on the internet about HFC cars potentially being scrapped because it's impossible to re-certify the tanks, or what a replacement tank might cost if this proved necessary.

The Mirai has two hydrogen tanks with a combined weight of 87.5 kg. A 45 kg or so tank isn't a big deal to move around in an automotive context (certainly compared to a 400-700 kg EV battery).

Again I doubt enough HFC cars have been scrapped to have any actual idea of the cost of recycling a small hydrogen tank - less than recycling an EV battery I would guess. As mentioned the tanks are always accessible from outside the vehicle so removal should be pretty straightforward, and commercial gas cylinders in general have been around for 100+ years so there must be well established procedures for emptying them at end of life.

There's certainly government guidance on dealing with scrap automotive LPG tanks, which I'd expect any legit breaker to be aware of:

After the tank has been removed from the vehicle, it should be placed on a suitable rack in a lockable wire cage in the open air for storage until a professional LPG operator can come in to empty and purge it ready for final disposal. Operators
may choose to wait until they have several tanks for disposal before calling in a specialist, in order to minimise the unit cost. A list of qualified LPG specialists with the necessary tank emptying or purging equipment can be found at ...

Removal of LPG tanks: guidance

Guidance for authorised treatment facilities on how to safely remove LPG tanks from end of life vehicles.

www.gov.uk

 

[poormansporsche]

So the first EV vans are in the Company for evaluation purposes.

As expected they are 3.4 tonne unloaded.

Hmmmm, so going to be 4.5 tonne loaded, which means a 7.5 tonne licence is required.

80 % of our drivers are under 45 the age you need to be to have got the 7.5 tonnes for "freeeeeeee"

Wonder if I'm going to paid "7.5 tonne money" ..............

Interesting times ahead

 

[BTB 500]

So the first EV vans are in the Company for evaluation purposes.

A lot depends on the usage/routes. They are fine for some applications, but there are good reasons why BEV vans only managed 5.8% of new registrations in 2024 ... lower than 2023, despite all the incentives etc.

 

[Bobby Dazzler]

A while ago I spoke to someone from Toyota who takes Mirais to promotional events like trade shows, car shows, community events. He was an employee but I’m not sure what his role actually is.

I asked about the life expectancy of a Mirai, and he said they don't publish any specific information on it but indicatively they expect it to be broadly similar to an equivalent ICE or EV.

I asked bow long that would be and he said 10-15 years, as that’s when major repairs and maintenance fall due which most owners would find difficult to justify the cost of performing them.

I asked about replacement of the fuel cell and onboard tank and he said they’re designed to last the expected life, but require regular safety checks beyond MOT and conventional servicing.

He also said that the life expectancy of ICE has been reducing in the last decade or so, and Toyota work on the same life expectancy across all drivetrains, so Hydrogen, EV, Hybrid and ICE.

No hard data but interesting to hear. I’m sure Toyota will have the data to support it. I suspect that it’s not a coincidence, they simply design all cars based upon the same life expectancy.

For those concerned about the longevity of EV batteries and cost of replacement, it sounds like Hydrogen Fuel Cells may offer an alternative but in a similar ball park in terms of service life.

The other interesting insight he told me is that Toyota don’t really see a big future in Hydrogen Fuel Cells for cars, their interest is for heavier applications like trucks, buses, etc.

 

[rf065]

Unlike the nice new BEV buses in Glagow then

Freezing weather disrupts Scottish city's electric buses leaving commuters stranded

THE freezing weather last week disrupted Glasgow's electric buses, causing their batteries to drain faster than usual, and leaving people…

www.thenational.scot

It's just got a whole lot worse, 30 out of the first 50 EV buses delivered have been removed from service due to some sort of structural issue. As Glasgow is a LEZ zone you cannot just use a diesel bus as a stopgap.

FirstBus Glasgow removes electric bus fleet from service after 'structural failure'

It is understood that the fault led to service cancellations, and bus spotters soon noticed that vehicles had been drafted in from as far as England to replace 30 new buses.

www.glasgowlive.co.uk

 

[markjay]

AFAIK Toyota's tanks (for example) are certified for 15 years - the expiration date is on the inside of the filler flap ("do not refuel after ..."). I assume they'd need to be re-certified at that point.

View attachment 166201

The tanks are constructed in 3 layers, the innermost of which is an inert plastic:

View attachment 166200

So not unlike airbags (when first introduced) or SBC pumps, then.....

 

[markjay]

It's just got a whole lot worse, 30 out of the first 50 EV buses delivered have been removed from service due to some sort of structural issue. As Glasgow is a LEZ zone you cannot just use a diesel bus as a stopgap.

FirstBus Glasgow removes electric bus fleet from service after 'structural failure'

It is understood that the fault led to service cancellations, and bus spotters soon noticed that vehicles had been drafted in from as far as England to replace 30 new buses.

www.glasgowlive.co.uk

I wonder if this is a chassis failure (Dennis) or a tech failure (BYD)?

Dennis have great reputation as UK coachbuilders, and BYD are probably the largest manufacture of EV LGVs and HGVs... interesting.

 

[markjay]

See also:

BYD–Alexander Dennis partnership delivers 39 electric buses to Stagecoach in Scotland | Alexander Dennis

Alexander Dennis and BYD UK jointly announced today that their electric vehicle partnership has completed the delivery of 39 zero-emission buses to Stagecoach. Alexander Dennis is a subsidiary of leading independent global bus manufacturer NFI Group Inc. (NFI), while BYD is a global leader in...

www.alexander-dennis.com

 

[markjay]

A quick Google search shows that these Dennis/BYD busses are everywhere....:

(I wonder if this means that in the event of war the Chinese can cripple our public transport? )

 

[Bobby Dazzler]

I just spotted a BYD Atto 3 in the wild. Ironically it was parked at a petrol pump whilst the driver sauntered around the shop.

 

[BIGDOG]

I just spotted a BYD Atto 3 in the wild. Ironically it was parked at a petrol pump whilst the driver sauntered around the shop.

I love a good saunter.

 

[Dryce]

I wonder if this is a chassis failure (Dennis) or a tech failure (BYD)?

Dennis have great reputation as UK coachbuilders, and BYD are probably the largest manufacture of EV LGVs and HGVs... interesting.

Maybe down to the state of Glasgow's roads.

The buses effectively get hammered continuously from below going over pot holes and other road damage and collapsed / sunk drain covers.