Alta Says Its Battery Packs Are More Energy Dense Than Tesla Model S, Likely On Par With Model 3

JUL 25 2017 BY MARK KANE 11

Charged EVs published a very interesting article about Alta Motors’ battery pack technology, that enabled it to achieve world’s highest energy density in an EV.

Alta Motors – 5.8 kWh battery pack

According to the Rob Sweney, Alta Motors’ Director of Advanced Powertrain, the 5.8 kWh battery in Redshift MX motorcycles is at around 180 Wh/kg density.

It would be 20-30% more than Tesla Model S battery, but is expected on par with the new Tesla Model 3 (2170 type cells).

Like Tesla in the Model S and X, Alta is using 18650 format cells, and is utilizing passive air cooling through a specially developed thermal design, with help of Wevo-Chemie (materials) and Scheugenpflug (custom production equipment).

“Kevin Kim, Alta Motors’ Mechanical Engineer: Unfortunately we can’t disclose too many details about the interconnect system because it’s proprietary. I will say that the system allows us to very effectively cool the battery using passive (air-cooled) methods, with no need for liquid cooling. We describe it as being passively air-cooled, and it helps keep the weight down significantly.

Passive cooling means that the thermal conductivity of the materials that surround the cells is very important. After some testing, we found that a two-part polyurethane from Wevo-Chemie (a German company for tailormade casting, bonding and sealing resin solutions) had the highest thermal performance, so it became a critical component in our system as an adhesive.

For any battery pack, you have to balance the need to take away heat from the system while dealing with the high-voltage electrical challenge. Usually things that are good at conducting heat are also good at conducting electricity. Optimizing for those two goals is a fundamental challenge of any battery pack design, so this implementation with the Wevo-Chemie material is part of our solution to improve that tradeoff, because it conducts heat extremely well and at the same time has a high dielectric strength – so it’s also electrically insulating.

It has good mechanical properties and is rated as flame retardant. It’s not super-stiff when it is cured, so it has mechanical give. And it was also cost-effective. All of these things made that a very desirable material.”

The challenge was in using the material in practice, but Scheugenpflug managed to deal with it:

“Kevin Kim: Basically, the resin has the consistency of peanut butter – it’s extremely viscous or thick. Also, the hardener component of the two-part mixture has a very low viscosity, about the consistency of water. That, [together with the challenging 100:8 mixing ratio of the material] makes it difficult to dispense.”

source: Charged EVs

Categories: Bikes, Tesla

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11 Comments on "Alta Says Its Battery Packs Are More Energy Dense Than Tesla Model S, Likely On Par With Model 3"

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Nice but there is no progres in cell chemistry, they are using the same cells as Tesla. And of course it is lighter because this pack does not need to be dimensioned for impending mechanical damage as a battery pack located under the vehicle.

The material they are speaking of is going to likely do a better job at protecting against a different kind of mechanical damage that would not be seen to such high level in a car. That is the intense mechanical jarring and vibrations inherent in an off road motorcycle. The solution they have is noted as having strength (a different material property than rigidity) and retaining ‘give’ which would help absorb some abuse that something like a Tesla pack might not be able to handle. It is not required to give structural rigidity in this application. So in other words it is everything they are saying it is. A Tesla has nowhere near the horsepower of a container ship. What a crappy car.

This news, plus a quarter, will get you cheap coffee.

And sell motorcycles. And perhaps can be used in other applications.

J.B Straubel says Energy Density at the pack level is kind of a meaningless number. For instance, in the Model S the battery pack performs a critical structural role in addition to being a battery, helping to protect the passenger cabin during a crash and giving the Model S the top rating in crashworthiness. The Alta Motors battery doesn’t protect the rider in any way whatsoever.

Does it use 2170 cells?

No. Propably about 500 cells.

Claiming a higher pack-level energy density by not using an active cooling system… that’s not really an achievement, unless you consider it an achievement to settle for less. It’s efficient in terms of cost and space, and space is very important in a motorcycle powertrain. But it certainly limits the ability to fast-charge the battery pack, and it means that the pack will quickly overheat if called upon to power sustained acceleration, such as a high-speed run up a mountain, or several racing starts in close succession.

Not sure about your statement.
As an ex motocrosser, I just don’t find anything that can ride as hard.
Your are basically always using max power all the time except on hard braking.
Totally opposite of car driving, where you very rarely apply all the power.
So, if this motorcycle can’t stand the abuse, there is no need to produce it.
Since they are produce and seem appreciate, the heat problem has been solve.

I’m certainly willing to be told my armchair engineering is wrong, by someone who has actually ridden this motorcycle hard and tested its limits.

Have you done so, Djoni? From your comments, I’m guessing that — just like me — you’re merely expressing an opinion based on your life experiences and common sense… and not based on any personal experience with this particular vehicle.

Oh I was hoping it was Altair Nano batteries. They are super powerful and my friend used to power his unbeatable electric dragster with them. The Current Eliminator, go Dennis.