Indian startup develops fast charging technology that can fully charge electric vehicles in 5 to 15 minutes

Although electric vehicle companies have solved the range problem a few years ago, they have not figured out how to make charging electric vehicles as fast as refueling gasoline vehicles. According to foreign media reports, a startup called Exponent Energy in Bangalore, India, said they have found a solution. The company claims that its technology can fully charge any commercial electric vehicle battery in 5 to 15 minutes, which is similar to the time it takes to refuel a gasoline car.

Electric vehicle charging (Image source: vccircle.com)

According to Arun Vinayak, co-founder of Exponent Energy (formerly chief product officer of electric vehicle startup Ather Energy), the technology does not require special batteries or battery chemistry and is compatible with existing ordinary lithium-ion batteries and other common batteries. The company will work with electric vehicle manufacturers and charging point operators (CPOs) to deploy its solution across India.

Vinayak co-founded Exponent Energy with the help of Sanjay Byalal Jagannath, Head of Hardware Strategic Procurement and Battery Strategy at Ather Energy.

Vinayak said: "It is fair to say that electric vehicles are indeed better cars, but they are still limited because of energy issues. On the one hand, charging station operators buy charging stations and connect them to the grid; on the other hand, OEM companies focus on producing batteries and cars. However, although there are cars and charging stations, the two parties are not working together, and the car takes 8 hours (or more) to charge, and the battery can only be charged and discharged 1,000 times."

To solve this problem, Exponent Energy has developed a flexible energy stack that combines software and hardware to increase charging speed. The company has also designed a patented battery management system (BMS). This common electronic system can be used to monitor, manage, store and supply electricity to electric vehicles. In simple terms, the BMS monitors how the battery pack is charged, the health of the different cells in the battery pack, and more.

According to Vinayak, nearly 50% of Exponent's technology is software technology, which can seamlessly and accurately control the flow of energy from the grid to the charger and then to the battery. And Exponent's BMS is 10 times more accurate than any BMS currently on the market. Electric vehicle batteries contain thousands of cells, and when the vehicle is connected to the power source, these cells may be at different charge levels. Exponent's BMS can understand the condition of the entire battery, including health, and can also create a customized charging profile for the battery to regulate the current flowing to the battery when charging.

The company also offers a warranty of 3,000 charging cycles for batteries charged with its technology. Vinayak said the company has tested a battery that was cycled 800 times, with each charge lasting 15 minutes and then discharged for an hour, and recorded a drop in capacity of less than 3.5%. When you charge a lithium-ion battery, some of its total capacity is lost. The industry standard for batteries is that if the degradation rate exceeds 20% after 1,000 cycles, the battery is dead. Generally speaking, one cycle is when a battery is charged from 0 to 100%.

Vinayak said: "In fact, fast charging is not new. It has been around since 2008. However, this technology must use battery chemistry, such as lithium titanate oxide (LTO) batteries, which are three times heavier and five times more expensive than the original ones, which is not commercially feasible."

Kavan Mukhtyar, partner and leader of automotive at PwC India, said while discussing the current charging system, “I think the alternative to fast charging right now is battery swapping, which is time-saving. Many companies are trying this route, especially in the two-wheeler industry, because in India, super or fast chargers are considered very expensive, and battery swapping is a more economical option as long as the theft problem can be solved.”

“There are some people trying things like fast chargers, but the key is how long does it take to charge and how much investment is required. At the moment, in most cases, the investment tends to be high. While there are certainly people trying this, I don’t think any products have been successful on a large scale [so far].”

Currently, even fast charging technology for smartphones requires an adapter that can quickly charge the battery and a battery that can charge quickly, or both. Exponent has two products, the e-pack and e-pump, which are basically battery packs and charging stations built with Exponent technology. Companies can continue to purchase batteries from existing suppliers and let Exponent add its own technology. Right now, most OEMs work with battery manufacturers that source cells and produce battery packs from China.

However, there are also investors who believe in Exponent's technology. The company has raised more than 70 million rupees (about 6 million yuan) in seed financing from investors such as AdvantEdge, 3one4 Capital and YourNest. Vinayak said the company will raise seed rounds in the next few months to bring the technology to market. He said that Exponent is focusing on working with commercial electric vehicle companies and has already established cooperation with several last-mile freight companies.