Good for drones too.
CATL has announced a new “condensed” battery with 500 Wh/kg
41–50 of 919 posts
Re: CATL has announced a new “condensed” battery with 500 Wh/kg
#42Why does 500wh/kg make electric aircraft possible? 6x less than kerosene. Is that the break even on cost if you can source very cheap electricity? Seems like it would still annihilate the payload/range.
Yep. Also... kerosene gets spent. Pilots can also dump fuel in emergency when it's too heavy to land. Battery powered planes can't dump electricity, so I'd imagine some trade offs that have to be made.
Electric planes could recharge using solar or wind. As efficiency increases with these technologies, it would mean planes wouldn't require carrying the same watt-for-watt energy as fuel.
Re: CATL has announced a new “condensed” battery with 500 Wh/kg
#43Earlier quoted context omitted.
Really it is encouraging for advancement areas like this. Reminds me of the "revolutionary battery checklist": https://news.ycombinator.com/item?id=28025930 edit: removed the paste of the checklist because of spam.
“No week goes by without a revolutionary battery technology” - Engadget, circa 2010
While this is true, a tiny start-up with big claims is different from the world's largest battery manufacturer (CATL) already spooling up production with the intent to scale.
Re: CATL has announced a new “condensed” battery with 500 Wh/kg
#44Cool! What didn’t occur to me until I learnt it was that you get a multiplicative benefit with energy density when weight is a major factor (air transport, especially) because you need to spend less energy accelerating mass used by the battery itself.
Same with jet fuel on a plane. They calculate the amount to fuel carefully to be efficient but safe. Too much and the plane is heavier and uses more fuel. Too little and you might run out if put into a holding then diverted.
Obviously jet fuel is what it is it wont get more dense but a more efficient engine means less fuel needed means even more efficiency and so on.
Re: CATL has announced a new “condensed” battery with 500 Wh/kg
#45Why does 500wh/kg make electric aircraft possible? 6x less than kerosene. Is that the break even on cost if you can source very cheap electricity? Seems like it would still annihilate the payload/range.
ICE engines only manage to turn ~15% of the stored energy in gasoline into actual work. A bit of googling suggests that jet engines are about 35% efficient. Stored electricity is much more efficiently turned into mechanical work... Electric engines have 75-90% efficiency. So, you get a lot more work or unit of stored energy.
That factor 6 already seems to include the efficiency of the engine. Pure chemical energy density of kerosene is 12000 W/kg, 24x the new battery's energy densitiy.
Re: CATL has announced a new “condensed” battery with 500 Wh/kg
#46"CATL has announced a new “condensed” battery with 500 Wh/kg which it says will go into mass production this year" This is a lot more credible than most of the battery stories, because CATL is already producing a ton of batteries, lending them some credibility. This is a little under 2x the density of current batteries.
My plan to buy an EV in the next five years may be realistic after all. Happy!
Re: CATL has announced a new “condensed” battery with 500 Wh/kg
#47Why does 500wh/kg make electric aircraft possible? 6x less than kerosene. Is that the break even on cost if you can source very cheap electricity? Seems like it would still annihilate the payload/range.
Well we had electric aircraft for half a century, but thats just toys. The variable is how many passengers can you fit.
Re: CATL has announced a new “condensed” battery with 500 Wh/kg
#48Cool! What didn’t occur to me until I learnt it was that you get a multiplicative benefit with energy density when weight is a major factor (air transport, especially) because you need to spend less energy accelerating mass used by the battery itself.
For a battery of arbitrary weight you need to spend the same amount of energy accelerating its mass, irrespective of how much energy that battery contains.
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Re: CATL has announced a new “condensed” battery with 500 Wh/kg
#49Earlier quoted context omitted.
The article mentions aircraft multiple times. Once a range is achieved through available energy, reducing weight is a goal. The energy is more useful the less weight you need to move as then you can shave off a bit more weight as less energy was needed. Your car may not need this as much, an aircraft does.
500-600 Wh/kg is the target for replacing average flight durations. Fuel is one of the highest costs for an airline, so eliminating the majority of that will make the demand for any viable options go bananas, even with a much higher upfront cost. Being seen as 'green' is a big bonus for the airline.
If the tech takes off (pun intended) every major airport will need a SMR. Which is maybe good? But politically impractical today.
Re: CATL has announced a new “condensed” battery with 500 Wh/kg
#50Why does 500wh/kg make electric aircraft possible? 6x less than kerosene. Is that the break even on cost if you can source very cheap electricity? Seems like it would still annihilate the payload/range.
Well, they were already possible and being sold. But with relatively short but usable ranges. Those now more than double with this battery. Which makes those planes usable in a lot more scenarios.
Consider the Eviation Alice, one of the 9 passenger prototype electrical planes that is currently undergoing test flights (i.e. it definitely works). The advertised range is 250nm. Not amazing. But far enough for a lot of regional flights.
What would happen if you double the battery capacity without increasing the weight? You more than double that range. This is counter intuitive until you realize that you are not going to need more energy for taking off, or reserves. All that extra energy goes into extending cruise range. So you get more than 250nm extra. Basically, it's probably getting closer to 600nm. That's still not amazing but there are a lot of flights every day that are much shorter than that. All of those are now doable with electrical planes. At a fraction of the fuel cost.
Most flights are short haul. And they are, well, short. Which means, all of those are in scope for electrical planes. Small planes work well for these too. You don't have to cram hundreds of people in a plane if you eliminate fuel cost as a major cost factor. That's the only reason we do that. It's not like it's pleasant or comfortable. 20 ten passenger planes can do the work of one passenger jet. But it can do it more flexible and cover more destinations too.
Electrical planes are not about doing exactly the same things that we do with traditional planes but about doing a lot more than that. Basically, less noise, less pollution, less cost, means that a whole lot of flights that would be considered decadent and obscene right now become perfectly feasible and reasonable. A ten minute hop across town. Why not? Live 70 miles from your office? Not a problem, you commute there in under 15 minutes. For the price of a few cups of coffee.