Lithium-air batteries

[widodh]

Combined with battery swapping, this would also be a solution for everyone without a garage for a charger: You'll bring it to the service station maybe once a month, and get a fresh battery within 5 min. Instead of an oil change, and faster.

That would work, but swapping would be limited to "Tesla stations".

Still, Lithium-Air seems to good to be true.

 

[Norbert]

That would work, but swapping would be limited to "Tesla stations".

Still, Lithium-Air seems to good to be true.

Personally I'm not too sure about Lithium-Air specifically. However in general my impression is that battery research is going somewhere in the near future, I'm quite optimistic. For example the currently fast developing Nanotechnology appears to be helpful in this regard.

 

[cinergi]

Interesting video in this link

The goal “is to create a battery that will power the typical family car about 500 miles between recharges,” explains Winfried Wilcke, Senior Manager, Nanoscale Science and Technology with IBM. “Today’s batteries…fall short of this goal by quite a factor, with [the best batteries] only lasting approximately 200 to 240 miles.”

http://scobleizer.com/2011/02/10/car-battery-of-future-inside-ibms-coolest-lab/

 

[Norbert]

Interesting video in this link

Certainly, thanks for posting. It's great to get an update on where they are.

 

[widodh]

Thanks! Seems they are getting somewhere, but it still take some time before we can start using it.

 

[Norbert]

IBM apparently expects an energy density of 1700 Wh/kg.

If the Model S 300 mile range battery is based on 280 Wh/kg and if the Lithium-Air battery would have the same weight, it would result in a 1800 mile range battery by comparison.

 

[widodh]

IBM apparently expects an energy density of 1700 Wh/kg.

If the Model S 300 mile range battery is based on 280 Wh/kg and if the Lithium-Air battery would have the same weight, it would result in a 1800 mile range battery by comparison.

Their goal is a family-sized car which will go 500 miles (800km) without a charge.

Let's say the EV will uses about 230Wh/KM, you would then need 184kWh of energy! With 1700Wh/KG that would be battery-pack of just 108KG.

But 184kWh in a car is a but to much imho, think about the time it would take to charge such a thing. It's more then 3 times the Roadster pack and two times the Model S 300 mile pack.

 

[Norbert]

Imagine driving into vacation and not having to charge until you are back. Or imagine in a few hundred years we'll have batteries which last a year and are swapped when the car is in for annual service.

 

[Iz]

But 184kWh in a car is a but to much imho, think about the time it would take to charge such a thing. It's more then 3 times the Roadster pack and two times the Model S 300 mile pack.

I would guess most people would do a full charge ~ 1x/week or month. Some might only charge a few hours and rarely "top off" to a full pack. This would have a positive impact on the grid, as not everyone will have a need to charge daily.

Or imagine in a few hundred years we'll have batteries which last a year and are swapped when the car is in for annual service.

If civilization has to wait several hundred years for a one-year battery, then our progress has slowed significantly. That goal should be attainable within the next 20-50 years. A small nuclear fission reactor in each vehicle should work nicely - on a glass of water.

 

[dpeilow]

But 184kWh in a car is a but to much imho, think about the time it would take to charge such a thing. It's more then 3 times the Roadster pack and two times the Model S 300 mile pack.

It's about an hour and a half on the proposed J1772 DC standard, overnight charge on a Tesla HPC. Not unmanageable.

 

[Talkredius]

It's about an hour and a half on the proposed J1772 DC standard, overnight charge on a Tesla HPC. Not unmanageable.

but quick charge in 1 1/2 hour means a power supply of 150 kW for each car to charge , perhaps I should buy some shares of transformator building companies ?:wink:

But you are right, it isn't unmanageable, at least for EU, which has a 3 phase power supply.

 

[dpeilow]

We've talked about it at length in other threads, but J1772 DC is proposed to support 120kW.

 

[Norbert]

How much one needs to charge is determined by how much one drives (and the EV's efficiency), not by the battery size. The battery size only determines how much is possible to charge in advance if desired. With a smaller battery, you still need to charge the same amount if you drive the same amount.

 

[bolosky]

If civilization has to wait several hundred years for a one-year battery, then our progress has slowed significantly. That goal should be attainable within the next 20-50 years. A small nuclear fission reactor in each vehicle should work nicely - on a glass of water.

That's Mr. Fusion, thank you. And wasn't that supposed to be 2015? Methinks we're way behind.

 

[SByer]

How much one needs to charge is determined by how much one drives (and the EV's efficiency), not by the battery size. The battery size only determines how much is possible to charge in advance if desired. With a smaller battery, you still need to charge the same amount if you drive the same amount.

+1. What he said. And unless you have a very unusually long commute, 240V30A service at home will be more than enough for once a week.

 

[dpeilow]

The 500 Mile Battery: Miracle or Myth?


Raises some interesting points.

 

[AndrewBissell]

I'll bet on conventional-ish lithium ion delivering 500 miles long before Lithium air, and with fast recharge to boot.

 

[Norbert]

The 500 Mile Battery: Miracle or Myth?


Raises some interesting points.

When reading this article, I started to have doubts (4kW charger?) long before arriving at the final sentence. But then it was clear.

Regarding the volume, the Model S is repeatedly mentioned to have lots of space available. Perhaps lowers the expectations for a simple replacement pack which could achieve "vacation" range, though, if the energy density per volume is really limited to 2x. For that, it might have to be a bit SUV-like, stacking two (or even 3?) packs on top of each other. Then they could run in parallel, allowing higher input and output. 2 packs would give 1000 miles with 60 kW, with the weight still being much lighter than "real" upcoming packs.

But then, another limiting factor might be cost. In any case, I'd hesitate to take my numbers from the article above, given the sentence it ends with. The Model S, as planned currently, will already surpass that "vision".

 

[Norbert]

http://www.greencarcongress.com/2011/07/mit-team-synthesizes-all-carbon-nanofiber-electrodes-for-high-energy-rechargeable-li-air-batteries.html

Increased the energy density to 2500 Wh/kg, but didn't solve the other problems yet. Although at 2500 Wh/kg, even a cycle life of 100 cycles could be interesting.

EDIT: An article from MIT itself: http://web.mit.edu/newsoffice/2011/better-battery-storage-0725.html

 

[bolosky]

http://www.greencarcongress.com/2011/07/mit-team-synthesizes-all-carbon-nanofiber-electrodes-for-high-energy-rechargeable-li-air-batteries.html

gravimetric energies up to ~2500 W h kgdischarged-1 at powers up to ~100 W kgdischarged-1

2500 Wh/kg divided by 100W/kg is 25h -- That is the minimum discharge or charge time for a cell is more than a day. That sounds bad, until you realize just how much charge you're getting in that amount of time.

If you build a car with ultracaps for power buffering (i.e., you accelerate using the ultracap and use them to hold the energy from regen) then you still need to have the batteries provide the cruise power plus a bunch to be able to go up hills. Say, 40-50 kW for a decent sized vehicle. 50 kW at 100W/kg is 500kg, which isn't absurdly bigger than the Roadster battery (~400kg, but that's counting the whole ESS, not just the cells). A battery this size would hold 1.2MWh, or over 3K miles at 400 Wh/mile (i.e., for a big, inefficient vehicle).

You could build a car (or even a long-haul truck) out of that. It would be complicated and expensive relative to batteries with 5x power density because you need the ultracaps, but if the batteries and the ultracaps were cheap enough, it could work. And, you could drive Seattle to Tampa on a charge.

And, 100 cycles of a battery this size is 300K miles, which seems fine.