This is huge, I’m really excited while writing this and don’t know how to begin, but here it goes.
If you’ve been reading my articles for a while you already noticed that I refuse to write about miracle batteries or electric cars, that are promised to arrive in a couple of years from now. Mostly because that kind of “news” undermine electric cars by implying that current technology isn’t good enough and also because in most cases they are nothing more than fairy tales. Volkswagen in this field is the world champion, no other company makes so many press releases about future electric cars. It gets ridiculous, especially when behind closed doors they try to push legislation to delay electric car’s adoption.
Back to what matters, the SolidEnergy battery and why this is the real deal.
When I try to figure if a to be released battery for electric cars is legit, I check what are the manufacturer’s plans to introduce it to the market. If it says that the amazing battery will go from the drawing board directly to electric cars, this is a big red flag and most likely the company will never deliver the battery. The most solid plan is always to start small and then increase the production. Smartphones are a great way to test new cells, since the battery is actually only one individual cell with daily use and abuse.
SolidEnergy’s plans for market introduction are simple and solid. First batteries for drones in November this year, then smartphones and wearables in early 2017 and finally electric cars in 2018.
I’ll definitely be paying attention to the smartphones that in 2017 will use these batteries.
Qichao Hu, the CEO of SolidEnergy said:
“With two-times the energy density, we can make a battery half the size, but that still lasts the same amount of time, as a lithium ion battery. Or we can make a battery the same size as a lithium ion battery, but now it will last twice as long.”
We can see what Qichao Hu means with the 2 Ah cell below:
The iPhone 6 has a 1.810 mAh battery with an energy density of 250 Wh/kg (gravimetric) and 575 Wh/L (volumetric). The SolidEnergy battery alternative is half the size and half the weight.
While SolidEnergy announces a volumetric energy density of 1.200 Wh/L for its market available cells, 1.337 Wh/L was achieved in the demonstrated 2 Ah pounch cell back in 2014, when it “was validated under industry standards by A123 Systems LLC”. This means that SolidEnergy is going by the “under-promise and over-deliver” premise or that the volumetric energy density was recently reduced to 1.200 Wh/L to improve other aspects of the cell, such as lifespan, power, cost or safety.
Regarding electric cars, Qichao Hu said:
“Industry standard is that electric vehicles need to go at least 200 miles on a single charge. We can make the battery half the size and half the weight, and it will travel the same distance, or we can make it the same size and same weight, and now it will go 400 miles on a single charge.”
What would you prefer, a Tesla Model S 100D that has a smaller and lighter battery, which makes it more efficient or a Tesla Model S 200D?
What actually means energy densities as high as 1.200 Wh/L and 400 Wh/kg for electric cars?
Let’s take the popular Nissan Leaf as example.
Each of the 192 cells in the 24 kWh battery has the following characteristics:
Capacity: 32,5 Ah
Nominal Voltage: 3,75 V
Weight: 787 g
Energy Density: 317 Wh/L and 157 Wh/kg
The 192 cells (192 x 32,5 Ah x 3,75 V) give a total battery capacity of 23,4 kWh. Yes, not the full advertised 24 kWh, you naughty Nissan! The 192 cells weight is 151,1 kg and the volume is 73,82 L.
With SolidEnergy cell’s energy density we could get:
With the same weight and less volume: 59,62 kWh and 49,68 L
With the same volume but more weight: 88,58 kWh and 221,45 kg
It would be great to see these cells produced in Tesla Gigafactory.
I’ve been saying than an automaker that uses cells with an energy density lower than 600 Wh/L doesn’t want electric cars to succeed. Now I have to rethink this figure and it might increase to 1.200 Wh/L sooner than later.
If you want to know more about SolidEnergy’s background read the MIT News article in the link below. It’s very well written and very interesting.