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[Francois]

do we wille have graphene batteri in the 2017 zero?
http://blog.evandmore.com/production-of-revolutionary-graphene-batteries-begins-in-spain/
 

[rayivers]

Amazing!  Maybe 2020...

Ray

[Say10 15FX 16FXS]

Recharged in one minute!?! Faaaaack!

[MrDude_1]

Recharged in one minute!?! Faaaaack!

Our batteries can be charged at a 1C rate already. That is, charged in a hour.  However the limiting factor is the DC charger... and once that is fixed, you're still limited on AC connectors that can supply that power... and once thats fixed, you're still limited at home by your house service connection to the grid... Its easy to pull too much with EVs in a modern home. Just run the dryer, start cooking dinner, and plug the EV in.

In otherwords, 100c charge rates are not going to happen easily. The largest limitation is the DC charger.

[gasdive]

Yes true, electrical supply is often the limiting factor. But Chademo has 50 kW charging. So we could charge at 4C. I'd be very happy if I could fill in 15 minutes.

However it's unlikely at this stage that the new batteries will match the old ones for energy density, which is an overriding factor for a motorcycle. Additionally, even if they were 95% efficient while charging, you'd still have to dissipate 2.5 kW of heat in 15 minutes, which means active cooling. Again, bulk and weight that we can't afford in a small package.

[Justin Andrews]

Gasdive, I've not seen the spec sheets, and news articles on batteries should carry a "may contain BS" stamp. However, putting that disclaimer aside, the first couple of paragraphs in the article are about the improved energy density of these batteries, and claims that they are ideal for electric motorbikes due to their reduced size over the current gen.

• Grabat’s battery is very safe with respect to fire.
• It can be recharged in less than a minute (100 C).
• It lasts four times longer than a Li-ion battery.
• It can store up to 1 kWh / kg (4 to 8 times more than a Li-ion battery)
• Its volume is 20% to 30% of that of a Li-ion battery (3 to 5 times smaller)

[/list]

All sounds a bit too good to be true.
So I'll wait till they are available for companies to put into their vehicles, until then, this looks and smells like another VC funding push to me.

[Erasmo]

Yes true, electrical supply is often the limiting factor. But Chademo has 50 kW charging. So we could charge at 4C. I'd be very happy if I could fill in 15 minutes.

However it's unlikely at this stage that the new batteries will match the old ones for energy density, which is an overriding factor for a motorcycle. Additionally, even if they were 95% efficient while charging, you'd still have to dissipate 2.5 kW of heat in 15 minutes, which means active cooling. Again, bulk and weight that we can't afford in a small package.

At this point, the connector is build to withstand 200A in future applications.

But at this point I'm more on the conservative side of graphene, it has been the wonder material for years but nobody has made a serious product out of the lab yet.

[MrDude_1]

But at this point I'm more on the conservative side of graphene, it has been the wonder material for years but nobody has made a serious product out of the lab yet.

The largest problem is no one has figured out how to make large sheets of it reliably.
The second largest problem is no one has figured out how to make it all in bulk.

Once we can reliably make it in bulk, applications will come faster with it... maybe not batteries right away, but I wont mind when I can order large farad caps from digikey and have them not be larger than my circuit boards.

[grmarks]

do we wille have graphene batteri in the 2017 zero?
http://blog.evandmore.com/production-of-revolutionary-graphene-batteries-begins-in-spain/
 

Following the link - that would mean a 30 kwh battery pack in a SR that weights 1/2 (battery weight) what it does now. Its about 2.3 times what a 2016 SR gets in range i.e. 299 km at 113 km/h.

(based on the fact that they quote a 5.7 kwh battery giving 100 km or range - sounds like a 2015 FX and by using volume not weight)

Many companies have made big claims, but we are yet to see any that have come to market.