[Shresth_EV]

Originally Posted by aim120

A Hydrogen tank is close to 10000psi pressure. A Hydrogen tank is even more dangerous due to more pressure.

Whether due to not knowing better or otherwise, I almost never saw a “how long does H2 car last” question.

When the user manual from Toyota itself stamps an expiry date on the tank from factory, beyond which they deem it unsafe to use and demand immediate replacement due to embrittlement.

Mirai user manual : https://gimmemanuals.com/owners/2022...ers-manual.pdf



This is just the tank, the fuel cell is said to degrade in performance if used in dusty environments with high particulate concentration (basically most metrocities)

Either the owners would be changing ion and air filters every week, or it would choke and refuse to run at all. I wonder how Gadkari Ji’s Mirai is doing in NCR air, if at all he uses it that is.

However, I have a hunch as to why it isn’t discussed — because the most useful PoI (the owners) flip off the vehicle as soon as the fuel card or lease or both expire on their Mirai, the former of which is good for around $15K or 40 thousand odd km when Mirai 2.0 launched.

So we kinda don’t have high mileage FCEVs in the first place which would require a tank or fuel cell refurbishment.

And I’m not inventing this info, I’m taking cues from what I read on r/mirai over at Reddit.

Link 1

Link 2

Link 3

[VSEV85]

Originally Posted by SKC-auto

Let's leave safety and infrastructure challenges aside. The cost of refuelling with H2 costs 36$/kg.

The current production cost of green hydrogen is around $3 today. RIL aims to reduce the production cost by half within ten years. They have invested heavily in green energy because they know that's the future. Lithium reserves around the world are being cornered by China. No one wants to depend on China.

[Shresth_EV]

Originally Posted by VSEV85

The current production cost of green hydrogen is around $3 today

The production cost doesn’t matter to end user, only the cost they pay does.

And as it stands, the $3/kg figure is not shown in the MID of the H2 dispenser at any filling station, while the former figure of $36/kg is.

Production is just the electrolysis part, $3 is about ₹250, at household rates, just enough to buy 31kWh electricity at ₹8/kWh.

If they have their own solar setup for RE, then the $3 is moot as they essentially make it for free barring NRE of the setup itself.

The real cost comes once you try to compress the said H2 to 700 bar for filling in the tanks of the trucks that transport them, the trucks themselves, and the H2 carried per truck is also an important metric.

A 4x2 tanker is usually 12kL and while 12kL is enough to refuel 300 cars, 12kL barely carries 600kg (assumed since Mirai carries 6kg in 120L — the real capacity will be much lesser as you can’t use that huge a unibody tank, rather many smaller tanks — like CNG is carried)

So even in best case scenario, 3x more trucks are needed for transporting “equal amounts of fuel” for hydrogen cars vs ice cars

The tanks at hydrogen stations are chilled to -20°C for ease of dispensing which again uses constant energy input (electricity)

Lastly, the powerful compressors needed for repressurising the tanks back to 700bar after every filling session also consumes energy.

So not only are there recurring costs for hydrogen beyond the production stage, these OPEX are higher than those for ICE supply chain. https://www.hydrogen.energy.gov/docs...?Status=Master

To make matters worse, even the CAPEX for each stage is higher — if you want to have production parity with oil ie 100% replacement of ICE with FCEVs — you need to spend more on the trucks carrying h2, the pumps selling it and the plants producing it. And not just in terms of the numbers, each individual pawn in the supply chain is costlier, be it the carbon fibre and Kevlar lined tanks at station and on trucks, or the PEM electrolysis machines. https://venair.com/en/blog/articles/...0million%20USD.

The $36/kg is inflated $33 more than RIL’s claims because it is actually including all these costs and probably also doing a last attempt recovering the CAPEX invested by the hydrogen startups like TRUEZERO into setting up these stations. That’s because the stations are shutting down left right and centre due to disuse and lack of H2 supply at many stations. They never know how much longer even the currently active stations will stay active — so minimising losses is their priority, not providing subsidised fuel.

https://h2fcp.org/sites/default/file...ng-Aug2016.pdf

[aim120]

More CNG tank failures in the below video, one can only imagine a Hydrogen tank failing. What if the Hydrogen car is involved in crash with a cement mixer truck, no amount of controlled crash test video can simulate such crashes and the way the sudden pressure is released means that it will look like a site of a bomb explosion.

https://youtu.be/TG0kncxOTEs?si=0kKMh_ClatY2kpbj

[Turbosailor]

Stumbled upon a good article in The Telegraph about Europe's vision on Green Mobility powered BEV.

Most of us admire how good Japanese engineering is, when compared to others. Need to commend the vision of Honda, Yamaha, Kawasaki & Suzuki for the association in Future Fuel research.

Below is the link to below article.

https://www.telegraph.co.uk/business...imbdown-begun/



Some important points from the article below,

[electric_eel]

Originally Posted by VSEV85

The current production cost of green hydrogen is around $3 today. RIL aims to reduce the production cost by half within ten years.

Production cost is bad but transportation/ storage is worse when it comes to hydrogen.

They have invested heavily in green energy because they know that's the future. Lithium reserves around the world are being cornered by China. No one wants to depend on China.

A simple difference is that Li extracted is for the entire life cycle of the battery pack + can be recycled after is life time. The H2 generated is for a single run; for the next run you need to generate it again spending enormous amount of energy; transported in special tankers, stored in special fueling stations each of which will cost millions of dollars (h2 is not a simple gas to store). There is no way H2 can be a replacement fuel and if you want to know what a terrible idea H2 is as a fuel see this (I have posted this multiple times)

https://youtu.be/JlOCS95Jvjc?si=cxR5g9Q4dxrfAvIq

It will explain in all detail how impractical h2 is as a fuel.

[Prado]

Originally Posted by ds.raikkonen

a Tesla which had caught fire which was put out by fire fighters subsequently, consumed 6,000 gallons of water in the process.

However, a day later, the car re-caught fire due to a hot spot somewhere deep in the battery system. THIS aspect disturbed me more than the fire itself, that you don't know for sure whether an EV fire has been put out or not.

As you rightly put, an EV fire due to a battery thermal runaway would require thousands of gallons of water to put it out.

Not only does the water cause lithium-ion batteries to combust, the minerals left behind after the battery packs dry out can spark fires days or weeks later . While it is much more likely an internal combustion engine will catch fire than an EV, such battery fires can be particularly difficult to fight. Despite years of development, fire departments are still shaky on how to handle EV fires. The usual move is to deny the fire oxygen, but that doesn’t work with lithium-ion, which can happily burn away without oxygen.

I had made bold a portion which is not really true. Pure lithium metal is highly reactive and flammable, however in the modern cells there is no pure lithium. It is present as lithium ions in various salts in different structural forms (NMC/LFP). Li ions are not unsafe, however the structural differences between NMC and LFP could make NMC more vulnerable. This could however be countered with appropriate measures in the design and software level.

When you pour water over a burning battery pack, it does not fuel the fire. What it does is helping bring the temperature down rapidly. It is in fact recommended to submerge the entire battery pack under water of that is possible.

The apprehension would be will water not cause internal short circuits? Well, the fact that the battery is burning itself could be due to some internal short circuit. Also, as long as the water is being contained within the battery pack, all short circuits are entirely internal and causes rapid discharge of cells. So it is helping put the fire out quickly.

In most of the battery fires caused due to thermal runaway, the culprit is the highly flammable and volatile liquid electrolyte in the cells. The white/grey fumes you see before a fire is not smoke, but often the electrolyte fumes. It catches fire at relatively lower temperatures as well. And there is no need to supply additional oxygen to sustain the fire as the cells themselves provide that. The objective while putting out an EV fire is hence to reduce the temperature, and water is the best possible solution. If the temperature of the battery/cells is maintained below the fire threshold, it will not reignite. Otherwise it will continue to burn till all the electrolyte is consumed.

Originally Posted by dragracer567

Two contradicting statements. Why would ICEs catching fire not shake the foundation of a reputed brand? Why would EVs catching fire not be due to poor maintenance (Human Error) or a design error that will eventually call for recalls in time?

We are giving ICEs the benefit of the doubt but not EVs. Shouldn't the goalpost be the same for both?

In my opinion, we must look at the battery pack as the counterpart of the fuel tank in an ICE vehicle. The electric motor is the counterpart of the IC engine (broadly speaking). So, if you see the vehicle itself as the goalpost, it is same. But if you look at the details behind the causes of fire, the goalpost is not the same I would say. If you look at the causes of ICE engine fires, hardly any would be there due to fuel catching fire as the cause of fire. It could happen as an after-effect, that too is rare. It is more often than not the electrical short circuits due to improper design or after-market fitments, poor service, etc. There have been cases or recalls where some plastic parts were near high temperature metal parts causing melting and subsequent fire. Whereas in a BEV, the battery pack itself could start a fire due to cell thermal runaway and propagation. Hence, it needs to be addressed at a more serious level in design itself, by adopting the appropriate safety measures based on the cell chemistry, failsafe application software, etc.

[alok9345]

Just some further data points when it comes to fire risks for various fuel types.

https://www.autoinsuranceez.com/gas-...ric-car-fires/

[Sam800]

My sources tell me today that Volvo has awarded new car to the owner. He took the delivery of brand new car of same model today.

One of my family member works for the company owned by the owner of car. I don't want to post about my sources much due to safety reasons.
Wishing him for safer drives

[dmaheshkumar]

Originally Posted by Sam800

My sources tell me today that Volvo has awarded new car to the owner. He took the delivery of brand new car of same model today.

One of my family member works for the company owned by the owner of car. I don't want to post about my sources much due to safety reasons.
Wishing him for safer drives

That was very good news for the customer.
But whether they have identified the reason for this Fire incident? Sorry if i am missing something, I could not able to view the reasons from Volvo side in the above posts.

[Sam800]

Originally Posted by dmaheshkumar

That was very good news for the customer.
But whether they have identified the reason for this Fire incident? Sorry if i am missing something, I could not able to view the reasons from Volvo side in the above posts.

Sorry, I don't have any information regarding it. I think Volvo will themself release it through their channel. As the issue has become national news

[nmn.070]

Any updates on this story? It is important that a fair explanation is provided for this incident. Consumer awareness is often incomplete and once it is out of sight it will allow dealers to provide their own narrative of the situation to prospective buyers.