Israeli startup has a battery that can charge an electric car in 5 minutes
https://thenextweb.com/insider/2017...e-an-electric-car-in-5-minutes/#.tnw_kULj8zal
https://thenextweb.com/insider/2017...e-an-electric-car-in-5-minutes/#.tnw_kULj8zal
Israeli startup has a battery that can charge an electric car in 5 minutes
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If I had a nickle for every time this claim was made, I could buy a Tesla.
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LOL...seriously.
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Sounds more like a supercap than a battery. Supercaps support vastly higher charge/discharge rates and much longer lifetimes than batteries, the problem is that their energy density is lower. If you could build a supercap with the same energy density as a lithion ion battery then it would be far preferable to a battery, unfortunately the energy density isn't there yet.
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Sounds like it's going to need some seriously fat cables.
I was thinking about the same thing. Assuming a Tesla sized battery, charging in 5 minutes instead of 75 means drawing 15x the power.
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Well, if you could tap a 1000 Volt line you could use a smaller cable. I don't seem to have any of those near my house. Maybe underground, I don't know.
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I'd priorize the battery issues as follows,
1) Cost. Bolt battery costs $9K, to sell without subsidies it needs to be $2K.
2) Density. Bolt battery weighs 900lbs and it's too small. A 3X improvement would drop the weight to 300lbs and the weight of a 120KWh battery to 600lbs. More importantly it makes 120KWh batteries reasonable, 120KWh gives the Bolt the same range as a Volt.
3) Durability. Lithium Ion batteries have to be babied. The Volt gives up 20% of capacity, the Bolt 10%, to increase the life of the battery. Charge/Discharge rates have to be limited and temperature has to be tightly controlled. Tesla drops the charge rates on their batteries after a certain number of supercharges. My guess is that the half sized charger in the Volt was chosen to improve battery life. The Bolt only charges at 6.6KW on Level 2 not 7.2KW and it's fast charger is only 50KW, my guess is that those were all tradeoffs to improve battery life.
4) Fast charge rates are the least important. A Tesla can get 100 miles in 15 minutes, ideally you might want to double that but you don't need to do any better than that. EVs are mostly charged at home so the only time you need fast charging is on superhighways. A 15 minute charge time is as good as it needs to be because it's enough time to take a leak and buy a donut. At that rate a fast charger will only be able to service 1/3rd as many cars as a gas pump but they are relatively cheap so the solution is to have three times as many of them.
Ideally you would want a supercap with several times the energy density of a lithium ion battery, don't know if that's possible. Lithium air batteries have 10X the energy density of lithium ions but they have much lower lifetimes so they aren't practical yet, hopefully that problem can be solved.
Agreed, but think about power stations (aka: gas stations) that had access to that type of high voltage line. Then you could drive your EV without any range anxiety since there could be a station on every corner like there is today with gas.
I think we all get that. My comment is simply that to deliver the same energy in 5 minutes that a Tesla gets from a supercharger in 75 minutes the charger has to deliver 15 times the power.
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300 miles in 5 minutes? no way!
The company claims 300 miles range charge in just 5 minutes.
Is that realistic? Is that possible? Let do a back-of-the-envelope to find out:
An EV runs at about 3.5 miles/kWh (Bolt), so for 300 miles their claim is a 86kWh charge in 5 minutes.
So that means the power rating of the charging cable needs to be (86X12) = 1032kW, more than a Megawatt!
The huge power density gives huge currents, and with that huge problems.
For a 360V DC fast charge the Megawatt implies a current of 2866 Amps (!). That is 14X the current rating of a large home fuse box. There is not even a wire gauge wide enough for those currents. The thickest 0000 (1/2 inch diameter) gauge wire would would melt in an instant.
So, even if a 86kWh battery exists that can fully charge is 5 minutes, there is just no practical way to get all that energy in.
But even if it existed, it would be hard to avoid the battery from exploding. Assuming a 5% loss due to internal battery resistance, the internal heat production would be ~50Kw. That is equivalent to 14 bug 3.5Kw space heaters.
There are other engineering challenges that need to be tackled. If fast charge is the only thing this battery is good at, it is likely bad at any or all of the following:
This is a sales pitch that only works on technically-challenged investors and some lazy journalists.
The company claims 300 miles range charge in just 5 minutes.
Is that realistic? Is that possible? Let do a back-of-the-envelope to find out:
An EV runs at about 3.5 miles/kWh (Bolt), so for 300 miles their claim is a 86kWh charge in 5 minutes.
So that means the power rating of the charging cable needs to be (86X12) = 1032kW, more than a Megawatt!
The huge power density gives huge currents, and with that huge problems.
For a 360V DC fast charge the Megawatt implies a current of 2866 Amps (!). That is 14X the current rating of a large home fuse box. There is not even a wire gauge wide enough for those currents. The thickest 0000 (1/2 inch diameter) gauge wire would would melt in an instant.
So, even if a 86kWh battery exists that can fully charge is 5 minutes, there is just no practical way to get all that energy in.
But even if it existed, it would be hard to avoid the battery from exploding. Assuming a 5% loss due to internal battery resistance, the internal heat production would be ~50Kw. That is equivalent to 14 bug 3.5Kw space heaters.
There are other engineering challenges that need to be tackled. If fast charge is the only thing this battery is good at, it is likely bad at any or all of the following:
- Self-discharge (should be less than 1%/day)
- Long life (needs to survive 3000 cycles)
- Charge/discharge losses (should be < 5%)
- Temperature range
- fire-safety
This is a sales pitch that only works on technically-challenged investors and some lazy journalists.
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To do 90KWh in five minutes you would need 3600V @50A. The line that distributes power to a neighborhood is 2400V (correct me if I'm wrong) so lets assume 2400V @50A which would provide 60A in 5 minutes which isn't totally ridiculous but it's still a scary high voltage.
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I''l jump into the could be wrong pool. My understanding is that our neighborhood (fairly typical modern) has a "low voltage" or "mains voltage" supply of 1kV to our distribution transformers which step it down to 240V split phase.
Primary distribution voltages range from 4 kV to 35 kV phase-to-phase (2.4 kV to 20 kV phase-to-neutral). Only large consumers are fed directly from primary distribution voltages.
Another Miracle Battery?
From a great "what's new" website, NewAtlas.com:
http://newatlas.com/storedot-flashb...ail&utm_term=0_65b67362bd-d800e0bea7-90153821
The race is on. Love it.
From a great "what's new" website, NewAtlas.com:
http://newatlas.com/storedot-flashb...ail&utm_term=0_65b67362bd-d800e0bea7-90153821
The race is on. Love it.
A 5 minute charge on a 300 mile battery, as claimed, would take a lot more current than is available anywhere people are currently charging cars. I imagine you would probably have to build charge stations that are next to and tap directly into an electric company distribution substation. These new batteries are still going to be slow to charge when charged at home, work, and most convenient locations. But it is still nice to see advancements here.
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4000 amps 1200kw
1.2 megawatts
Power station for an entire community could run a 100 chargers
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