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The problem is primarily that batteries are storing a lot of energy, which can be released when things go wrong. The electrolytes (technically, the solvents) typically don't ignite under 750°F or so, which makes them less flammable than a lot of other common materials, and far less of a concern than, say, the lithium metal.
The flavour you want is polymer, single ion conducting solid state with an ion transport activation energy below 10kJ/mol at room temperature and no phase transitions from -40C to 80C.
That is the holy grail of SS batteries.
Well that's fine for terrestrial use but aerospace needs that range to be expanded a little in both directions, otherwise it won't be much of a holy grail if it won't cover the needs of one of the largest growing industries.
A good place to start would be a BMS on individual cells that monitors them for general degradation, unexpected discharge, unexpected temperature changes, and can remove a failing cell from the array.
Theres a handfull of Tier 1 BMS chips that support it already. though, half of them are meant for traction/EV packs instead of BESS.
And it's still improving at about 5% per year.
Speaking of nuclear, getting tons of the material that powers mars rovers and putting them in every home would generate enough power for decades... At the cost of being able to build a nuclear bomb in a garage.
I live in western Pennsylvania and have both natural gas and electric service, a roof and 1/3 acre of land to utilize. I would love to get rid of at least one of my utility bills and I’m becoming more interested in decoupling from the electric grid than natural gas service. I dream of a future where competition comes to monopoly utilities by way of direct competition with each other as there is a not so far off future where I can utilize solar, batteries and a natural gas fuel cell to cut ties with my Electric Utility. If that kind of competition can exist then the game is on for those utilities to start fighting for customers.
If energy is cheaper than the price of water you can pull water out of thin air (dehumidifiers).
If energy is cheaper you can grow food in areas you normally couldn't.
When you can transport anything for cheap you can move food to areas that are vulnerable to food insecurity.
If you can store energy at large scale you can nearly eliminate grid failures, savings lives in the summer and winter.
Costs for transporting food would go down significantly, imagine groceries being 10-15% cheaper.
Assuming airlines have competitive pressure you could expect plane flight costs to drop 20-30% improving everyone's mobility.
But it IS crucial for removing bottlenecks & replace fossil fuels.
Electric long distance container ships.
Useful portable laser, coil- and rail- guns.
Even longer range drones.
The Watt-hours per kilogram of good Lithium Ion batteries is around 250-280 Wh/Kg; for Lithium Iron Phosphate it's about 180 Wh/kg, and for Sodium-Ion about 170 Wh/Kg.
The raw energy in gasoline is about 12,300 Wh/Kg but automobile internal combustion engines get only about 20-30% efficiency yielding about 2500-3600 Wh/Kg. For aviation piston engines it is a bit better at 25-30$ so 3000-3600 Wh/kg.
So, the batteries, instead of being 10-12X the weight of the gasoline for the same net driving/flying range, could weigh about the same as the gasoline. So, a typical car with maybe a 16 gallon tank and 30 miles per gallon fills up with 128 pounds (58 kg) of gasoline to get 480 miles of range. The Li-Ion battery for that range would weigh something like 1300 Lbs (590 kg). That is a substantial additional weight for a car that could be 2800-3800 Lbs in ICE configuration, so 35-45% added weight (a bit less because of savings on the ICE engine, etc). This requires everything else to also be heavier, from the structural frame, the suspension system, and even the wheels and tires (which is also unsprung weight, further impairing performance).
With a 130Lb/60kg battery instead, and saving the weight of the ICE engine and fuel system, the overall car design could go much more lightweight, regaining a lot of performance and range, all while gaining the huge torque of electric motors.
In aviation, a battery systems of that weight would enable all-electric aviation to go from small performance niches to the default for general aviation.
So yes, it would be a HUGE benefit to achieve 10X energy density batteries, and we do have reference points for people to imagine it.
I think you're underselling it, even. A typical like-for-like modern EV is only marginally heavier than the ICE equivalent. If we were able to drop the weight of the battery by a thousand pounds, cars would be lighter than they have been in decades while retaining all the modern safety and convenience features we've come to expect. And if density improved along with weight, we could make EVs with the same form factor as today but with over a thousand miles of range. Not that we need that, but it is just as a tiny example of how mind boggling the game change would be.
As it is I've only recently internalized the notion that the most powerful electric tools are battery powered (what can I say, I grew up when rechargeable batteries were NiCad and they basically sucked). And it will just get better and better as time goes on.
A 1 GWh grid scale battery takes up about 4 hectares at the moment. The UKs total energy use is about 2,000GWh a day.
It would need to use 240,000 hectares to store all energy requirements (eletric, transport, heating etc) for a whole month. Even in extreme cold conditions it would last a couple of weeks.
That would be about 1% of land use.
I am surprised they didn't point out the literal "killer app" - military drones. Energy density is king for any airborne power source. And dendrite growth during charge/discharge cycling isn't as big a deal for that application (how many times would you need to charge a disposable weapon?)
- WW2 proximity fuzes that had batteries where the electrolyte was in a vial that got smashed by the G-forces of being shot out of a cannon providing power to the radio inside for the 10 seconds it needs to get to the incoming aircraft
- Hearing aid Zinc-Air batteries, that are extremely energy dense because you only have to actually manufacture the anode, the cathode is the entire atmosphere of the Earth
- Missile batteries, which are often Lithium-silicon/Iron Disulfide batteries that borrow some thermal energy from the rocket motor to get a molten salt electrolyte
Ambri was working on large scale batteries which seemed like a pretty good idea (looks like they ran out of money): https://en.wikipedia.org/wiki/Ambri_Inc.
https://www.sciencedirect.com/science/article/abs/pii/S20954...
https://youtu.be/xQFVIs4leig?si=iOOt5gg_2MJAIoFR
The energy density scatter plot is physically correct but misleading and everyone makes this mistake.
From an engineering point of view you have to use work delivered at the end of the drive train not fuel raw energy content.
When you do that lithium ion batteries compare more favorably to liquid fuels. That’s because the conversion path is more than 90% efficient. For ICE engines you’re starting with only 20-40% Carnot efficiency (depending on how good and in good shape the engine is) and then losing in the transmission and then losing more because ICE cars have more other gears and moving parts. Power to wheel is pretty terrible. Most of the energy from gasoline heats the air around the car.
This is also why you get outrageous sounding but accurate things like: an EV charged on 100% coal fired electricity emits less carbon than a typical gasoline car. The fact that coal is literal pure carbon fuel is made up for by the high thermal efficiency of a giant supercritical steam turbine vs a small piston engine. Coal burns real hot too (steeper thermal gradient). So more of the energy from coal ends up doing actual work vs heating the air. (Well directly heating the air I mean.)
For example, no need to build natural gas infrastructure to every home. Use induction stoves (or electric coil -- already 67% of homes). Heat pump water heater instead of gas. And heat pump for HVAC.
If all energy bills are consolidated as electricity (instead of gas, natural gas and electricity), most people would install solar on their rooftops, buy EVs, and save ~$1000/month on energy bills.
This isn't true at all for natural gas. Burning it for heat in the home is much more efficient than burning it in a plant, converting it to electricity, transferring that electricity, then turning that electricity into heat.
Heat pumps are significantly more efficient than 100%. They can get to 500% efficiency. So no, it's definitely not more efficient to burn gas in a home. (To say nothing of the safety of running gas lines to every house.)
is LiFePo4 immune to dendrite shorts? Or do they happen just don't burn?