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They claim 150Wh/kg - that's well below the best lithium ion cells, I think. If I am not mistaken, Lithium Ion cells reach more than 200Wh/kg nowadays and are d

They claim 150Wh/kg - that's well below the best lithium ion cells, I think. If I am not mistaken, Lithium Ion cells reach more than 200Wh/kg nowadays and are definitely capable of reaching 300Wh/kg.

brightball 5y ago
Seems like the lack of need for cooling weight would make up for the difference.
- altcognito 5y ago
  This is close to on par with Lithium ion (cobalt/nickel) 200-250Wh/kg. Newer Li/S technology is 2x denser (400-500Wh/kg) but currently has durability issues over recharge cycles. Al/graphene in this form could be more cost effective and probably marginally lighter due to a lack of cooling/heating needed, safety equipment, and rare earth minerals needed. That it charges faster and has more durability over recharge cycles would be a bonus. Another open question is if you can produce this at industrial scale relatively cheaply, because having affordable gigawatt storage for renewables would be lovely. This: https://finance.yahoo.com/finance/news/gmg-graphene-aluminium-ion-battery-200435268.html https://finance.yahoo.com/finance/news/gmg-graphene-aluminiu... may be a better article. Here is a clarifying quote: > Dr Ashok Nanjundan, GMG’s Chief Scientific Officer, said, “This is a real game-changing technology which can offer a real alternative with an interchangeable battery technology for the existing lithium-ion batteries in almost every application with GMG’s Graphene and UQ’s patent-pending aluminium ion battery technology. The current nominal voltage of our batteries is 1.7 volts, and work is being carried out to increase the voltage to directly replace existing batteries and which lead to higher energy densities.” > “The real differentiator about these batteries is their very high power density of up to 7000 watts/kg, which endows them with a very high charge rate. Furthermore, graphene aluminium-ion batteries provide major benefits in terms of longer battery life (over 2000 charge / discharge cycles testing so far with no deterioration in performance), battery safety (very low fire potential) and lower environmental impact (more recyclable),” said Dr Ashok Nanjundan.
  - jeffbee 5y ago
    Aren't energy density, weight, and bulk all irrelevant in large-scale fixed service?
    - altcognito 5y ago
      Within limits, otherwise pumping water uphill would be more common as an energy storage technique. The durability, operation at all temperature, and use of common, "easily" obtained ingredients are very relevant though.
      - bagacrap 5y ago
        I see lots of water towers in Texas.
        reportingsjr 5y ago
        Water towers aren't even close to the scale needed for reasonable energy storage. A typical water tower holds about 4 million liters of water and is about 50m tall. The Racoon Mountain Pumped Storage reservoir holds 410 BILLION liters of water (so 410 thousand times what a water tower holds) and has a head of 320m. So you'd need about 1.6 million water towers with energy extraction capability to be equivalent to just that one pumped storage plant, ignoring the fact that you'd have to do /something/ with that water to extract the energy at the right time, when typically it's just drained out as people need it for faucets/showers/whatever. On top of this, you'd be dropping a lot of the pressure from the water tower, which is like 99% of the reason that water towers exist, to provide adequate water pressure.
- SketchySeaBeast 5y ago
  The other consideration for myself when it comes to electric vehicles is charging time - I used to semi-regularily drive ~500 km to see my parents. Most electric vehicles would struggle with that and make me consider a recharge. Even if I have to fill up one or two times on the trip if the time it took was the same as filling up a tank of gas it'd make me much less reluctant. The question there of course is if the power grid could support that much power that quickly. I suppose it would need it's own aluminum-ion tanks that charged continually throughout the day.
  - ianai 5y ago
    Agree. I worry manufacturers are going to consider a range near 300 miles or 500 km “enough”. Many people in the US at least live in rural places where a 300 mile round trip might be needed weekly or even daily (for “shorter” distances like 200 miles that could still challenge a battery on a hot/cold day).
    - DennisP 5y ago
      I would bet that Tesla will make an extreme-range electric car whenever they can, just to show off. They're already at 500 miles on the high end. You might be right for other companies though, until Tesla proves extreme range has a market and they have to catch up again.
    - zamalek 5y ago
      You wouldn't need fast charging for a 300mi trip, assuming you had level 1 charging at your destination. 300mi daily may be too much for at-home level 1, but at-home level 2 (washer/dryer plug) isn't hard to install at all.
  - elif 5y ago
    That's a good point. Current LI Teslas recharge times are bounded by the charging stations, and not the batteries. Non-tesla charging stations are even worse, and become buggy when trying to charge the mach E at the rate the vehicle attempts.
lmilcin 5y ago
First of all battery technologies tend to get better over time. Second, many times faster charging speed is nothing to ignore. It means you can charge on many more occasions and you don't have to stop the car. Think you could stop your car by the side of the road and be on your way in matter of a minute. Ability to charge cars fast is a huge problem because not only they need charge more frequently than feuling they need so much more time to do it. If you calculate, replacing all cars with EVs would require a lot of space to park cars and to guest the people that need to wait for the car to get charged.
- jacob019 5y ago
  But where are you going to find a 500kW charger? Maybe if you put a complex and expensive supercapacitor bank in the charger, but then the charger will need to recharge between charging sessions. And what guage of copper will you need to push over 1000A? You would probably need to hook up a bunch of parallel cables to charge at that rate.
  - rini17 5y ago
    The supercharger will likely have the same Al-ion battery. And there's still untapped potential of using high voltage, when 10kV switching is possible with recent semiconductors, then to get 500kW means only 50A current.
    - thatfrenchguy 5y ago
      You're not going to have the generation capacity for this to be useful though. For your users it's nicer to have 4 x 150kw stations than 1 600kw station.
      - rini17 5y ago
        If users are willing to pay 10x normal price of electricity for 600kw supercharging - and why not, that is still comparable price to fossil fuels on basis of added distance - the generation and improved grid will certainly appear.

They claim 150Wh/kg - that's well below the best lithium ion cells, I think. If I am not mistaken, Lithium Ion cells reach more than 200Wh/kg nowadays and are definitely capable of reaching 300Wh/kg.

brightball 5y ago

Seems like the lack of need for cooling weight would make up for the difference.

altcognito 5y ago
This is close to on par with Lithium ion (cobalt/nickel) 200-250Wh/kg. Newer Li/S technology is 2x denser (400-500Wh/kg) but currently has durability issues over recharge cycles. Al/graphene in this form could be more cost effective and probably marginally lighter due to a lack of cooling/heating needed, safety equipment, and rare earth minerals needed. That it charges faster and has more durability over recharge cycles would be a bonus. Another open question is if you can produce this at industrial scale relatively cheaply, because having affordable gigawatt storage for renewables would be lovely. This: https://finance.yahoo.com/finance/news/gmg-graphene-aluminium-ion-battery-200435268.html https://finance.yahoo.com/finance/news/gmg-graphene-aluminiu... may be a better article. Here is a clarifying quote: > Dr Ashok Nanjundan, GMG’s Chief Scientific Officer, said, “This is a real game-changing technology which can offer a real alternative with an interchangeable battery technology for the existing lithium-ion batteries in almost every application with GMG’s Graphene and UQ’s patent-pending aluminium ion battery technology. The current nominal voltage of our batteries is 1.7 volts, and work is being carried out to increase the voltage to directly replace existing batteries and which lead to higher energy densities.” > “The real differentiator about these batteries is their very high power density of up to 7000 watts/kg, which endows them with a very high charge rate. Furthermore, graphene aluminium-ion batteries provide major benefits in terms of longer battery life (over 2000 charge / discharge cycles testing so far with no deterioration in performance), battery safety (very low fire potential) and lower environmental impact (more recyclable),” said Dr Ashok Nanjundan.
- jeffbee 5y ago
  Aren't energy density, weight, and bulk all irrelevant in large-scale fixed service?
  - altcognito 5y ago
    Within limits, otherwise pumping water uphill would be more common as an energy storage technique. The durability, operation at all temperature, and use of common, "easily" obtained ingredients are very relevant though.
    - bagacrap 5y ago
      I see lots of water towers in Texas.
      - reportingsjr 5y ago
        Water towers aren't even close to the scale needed for reasonable energy storage. A typical water tower holds about 4 million liters of water and is about 50m tall. The Racoon Mountain Pumped Storage reservoir holds 410 BILLION liters of water (so 410 thousand times what a water tower holds) and has a head of 320m. So you'd need about 1.6 million water towers with energy extraction capability to be equivalent to just that one pumped storage plant, ignoring the fact that you'd have to do /something/ with that water to extract the energy at the right time, when typically it's just drained out as people need it for faucets/showers/whatever. On top of this, you'd be dropping a lot of the pressure from the water tower, which is like 99% of the reason that water towers exist, to provide adequate water pressure.
SketchySeaBeast 5y ago
The other consideration for myself when it comes to electric vehicles is charging time - I used to semi-regularily drive ~500 km to see my parents. Most electric vehicles would struggle with that and make me consider a recharge. Even if I have to fill up one or two times on the trip if the time it took was the same as filling up a tank of gas it'd make me much less reluctant. The question there of course is if the power grid could support that much power that quickly. I suppose it would need it's own aluminum-ion tanks that charged continually throughout the day.
- ianai 5y ago
  Agree. I worry manufacturers are going to consider a range near 300 miles or 500 km “enough”. Many people in the US at least live in rural places where a 300 mile round trip might be needed weekly or even daily (for “shorter” distances like 200 miles that could still challenge a battery on a hot/cold day).
  - DennisP 5y ago
    I would bet that Tesla will make an extreme-range electric car whenever they can, just to show off. They're already at 500 miles on the high end. You might be right for other companies though, until Tesla proves extreme range has a market and they have to catch up again.
  - zamalek 5y ago
    You wouldn't need fast charging for a 300mi trip, assuming you had level 1 charging at your destination. 300mi daily may be too much for at-home level 1, but at-home level 2 (washer/dryer plug) isn't hard to install at all.
- elif 5y ago
  That's a good point. Current LI Teslas recharge times are bounded by the charging stations, and not the batteries. Non-tesla charging stations are even worse, and become buggy when trying to charge the mach E at the rate the vehicle attempts.

lmilcin 5y ago

First of all battery technologies tend to get better over time. Second, many times faster charging speed is nothing to ignore. It means you can charge on many more occasions and you don't have to stop the car. Think you could stop your car by the side of the road and be on your way in matter of a minute. Ability to charge cars fast is a huge problem because not only they need charge more frequently than feuling they need so much more time to do it. If you calculate, replacing all cars with EVs would require a lot of space to park cars and to guest the people that need to wait for the car to get charged.

jacob019 5y ago
But where are you going to find a 500kW charger? Maybe if you put a complex and expensive supercapacitor bank in the charger, but then the charger will need to recharge between charging sessions. And what guage of copper will you need to push over 1000A? You would probably need to hook up a bunch of parallel cables to charge at that rate.
- rini17 5y ago
  The supercharger will likely have the same Al-ion battery. And there's still untapped potential of using high voltage, when 10kV switching is possible with recent semiconductors, then to get 500kW means only 50A current.
  - thatfrenchguy 5y ago
    You're not going to have the generation capacity for this to be useful though. For your users it's nicer to have 4 x 150kw stations than 1 600kw station.
    - rini17 5y ago
      If users are willing to pay 10x normal price of electricity for 600kw supercharging - and why not, that is still comparable price to fossil fuels on basis of added distance - the generation and improved grid will certainly appear.