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Your Polestar 2 battery is based on battery technology that is 5+ years old. Right now you can buy a BYD car in China that charges at up to 1500kW - close to 10x the peak charging rate of a Polestar 2.
I’m an automotive EE… I find particular interest when someone mentions BYD as what “works” in electric vehicles. Wild fucking west right there.
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Gasoline has 10x the energy (MJ/Kg) than TNT, but it's not a "bomb". Being a "bomb" is about energy release rate . A battery is still controlled by its chemistry.
One of the problems with gasoline is its explosive nature, which the fuel storage and delivery system of a car attempts to mitigate. It has a better profile for burning off than a battery though since it will spill out and burn away from the vehicle.
"Petrol and diesel can only explode when under pressure and mixed with air and in the case of petrol, have a small amount of energy added in the form of a spark or a flame. Engines pressurise the fuel/air mixture in the cylinder and so produce small, confined explosions which turn a crankshaft and drive the wheels."
"When cars are involved in collisions, fuel lines are often torn and petrol leaks out onto a hot engine. Liquid petrol can catch fire in the presence of air. But it can’t explode because it’s not under pressure and is in the liquid phase rather than a vapour."
https://theconversation.com/fast-x-why-cars-dont-really-expl...
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"Liquid gasoline does not have anywhere near the energy of TNT," Energy density of gasoline is approximately 44 to 45 megajoules per kilogram. Energy density of TNT is approximately 4.184 megajoules per kilogram.
A snickers bar has nearly 5× TNT’s energy per kilogram—TNT merely has the habit of being extremely impatient about releasing it.
Solid state batteries come in several flavours. Most of them don't stop dendrites. 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.
Are anyone building the battery you described?
Solid state batteries come in several flavours. Most of them don't stop dendrites. 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.
I’m still a novice on the material science behind it, but what is QuantumScape lacking here if anything, and why is it a dealbreaker?
Perhaps a polymer will be invented that can’t be pierced by dendrites. But existing polymers need to be heated for ion transfer efficiency and are combustable.
Technically, QuantumScape also uses an organic liquid catholyte inside the cathode. So it’s not “pure” solid state.
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Liquid gasoline does not have anywhere near the energy of TNT, or even a battery for that matter. It contains basically zero releasable energy. It needs oxygen or another oxidizer to react with to actually release any energy. TNT and batteries' energy density calculations include the oxidizer and the oxidizer is in close proximity to the fuel (molecularly so in the case of TNT). If you 10x the "energy content" of gas…
"Liquid gasoline does not have anywhere near the energy of TNT," Energy density of gasoline is approximately 44 to 45 megajoules per kilogram. Energy density of TNT is approximately 4.184 megajoules per kilogram.
https://en.wikipedia.org/wiki/Table_of_explosive_detonation_...
There is a way how to use the energy density of gasoline for explosive purposes, Thermobaric weapons.
"A fuel–air explosive (FAE) device consists of a container of fuel and two separate explosive charges. After the munition is dropped or fired, the first explosive charge bursts open the container at a predetermined height and disperses the fuel in a cloud that mixes with atmospheric oxygen (the size of the cloud varies with the size of the munition). The cloud of fuel flows around objects and into structures. The second charge then detonates the cloud and creates a massive blast wave."
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The previous point is fair though. What is the energy density of gasoline in a stoichiometric mixture with its oxidizer and not already detonated? That's where TNT beats it by a long shot. The mixture with any chance of being stored would be some relatively low pressure gas. Edit: Or, a fair closed-system comparison to a battery would need to include a liquid oxygen tank or similar so you have the two components stor…
Air is usually quite available though.
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Gasoline isn't that explosive. You can shoot up a gas tank and it will just burn. What you see on TV is movie magic. Gasoline vapor can explode, but you need the right air to fuel ratio and a spark.
Uh… gasoline has a super high vapor pressure. If you start out at the wrong ratio, it does what it can to make that ratio right. I’ve seen a few gasoline fires that start by burning, and then much more rapidly expressing potential.
They did get it to happen, they just had to try really hard.
In most accidents the gas tank will not blow up.
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Less weight (all else being equal) is the same thing as more battery for drones. I.e. better range, payload mass, and/or flight time. You probably want both cheap and poor performing as well as expensive and high performing available.
In current battle conditions isn’t the range primarily determined by the size of the fiber optic spool attached to the drone than battery capacity?
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> We can extract a lot more energy from fossil fuels in large scale plants 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.
In addition the sibling comments (COP of heat pumps is 500%), air pollution in homes is worse than air pollution outside. If you don't have natural gas and burning fuel, it helps a lot. Not only is electricity cheaper and cleaner, but also healthier.