One of the biggest issues with electric cars is that recharging the batteries takes so much time. Using a normal wall socket you’d need anything between 4 to 8 hours to be ready for another 100 miles. No wonder the fan base of electric cars is growing so slowly. No, actually, the main issue with today’s batteries is at the core of their design. They’re simply built in a wrong way. When we look at the energy storage and management system of an electric car, the bulk of it does no job – it’s just cooling devices, supporting materials and ancillary systems – all the things that don’t store energy but still have to be carried with you wherever you go.
It doesn’t have to be like that. The wind of change is blowing from Massachusetts. Under the wing of MIT (Massachusetts Institute of Technology) two different future battery technologies are being developed.
Thinner than Usual
A journey into solid-state physics was started by Ann Marie Sastry – the brainpower behind a startup company Sakti3. They have developed solid-state batteries for electric cars that are still based on lithium-ion technology but there is no liquid electrolyte. Instead, there’s a thin layer of special non-flammable material.
Unlike the majority of great science ideas, this is actually feasible. You can make batteries that are half the size and three times cheaper than normal li-ion batteries.
General Motors are interested in Sakti3’s findings and have invested $3 million in the hi-tech start-up so far.
A more recent development is fronted by a trio of scientists and entrepreneurs: Yet-Ming Chiang, Craig Carter and Throop Wilder. Known together as 24M Technologies – another start-up that has a backing of as much as $16 million in Government subsidies and venture capital.
Professor Chiang has combined two rather common battery technologies in one super-powerful device. It merges the best features of li-ion batteries and flow batteries. Solid compounds of a li-ion battery are turned into a fluid suspension with particles – just like in a flow battery.
The “energetic” suspension looks like crude oil and the particles it contains actually perform as positive and negative electrodes. They are pumped through the system via a special membrane. Just like Ann Marie Sastry’s battery, the semi-solid flow cell developed by Chiang’s team, uses an entirely new architecture. It eliminates the shortcomings that the conventional li-ion batteries inherit by design – meaning that your common li-ion battery uses the same structure to store and discharge energy. With the semi-solid battery these functions are separate hence more efficient.
The brilliancy of this new technology is that you can recharge your electric car almost as quickly as a petrol car. The inactive “energetic” suspension gets pumped out and new volume of fresh “activated” suspension is poured in. You’re set and ready in almost no time.
Traditional flow batteries (although not very efficient) are relatively cheap to produce. It seems that 24M’s new battery has inherited it’s grandpa’s best features – it is cheaper than a li-ion to produce, provides a longer range and can be recharged in minutes not hours.
This is really exciting. MIT is on the course of changing our perception of electric cars forever by solving two problems simultaneously – making the batteries cheaper and getting more miles out of less bulk.