Exponent Energy, an energy-tech start-up, unveiled the tech behind its 15-minute rapid charging solution for the EV industry. It showcased its proprietary energy—battery pack (e^pack), charging station (e^pump) and charging connector (e^plug). 

Together, these can unlock a 15-minute rapid charge and long battery life (3000 cycle life warranty, three times the industry standard), all done on regular LFP cells for the first time in history.

Rapid charging kills range anxiety and the need for expensive, oversized battery packs. With this unique two-sided approach, EVs powered by Exponent will be 30 per cent more affordable, made possible by an optimised battery capacity (30 per cent smaller), and five-year financing (powered by 3000 cycle life warranty). Additionally, 15-minute rapid charging reduces EV charging costs by 33 per cent.

Exponent's energy stack addresses two key problems that, for decades, prevented rapid charging on LFP cells – Lithium plating and Extreme heat. 

When charging a cell, Li-ions flow from the cathode to the anode and get absorbed. The faster you charge, the more ions flow, leading to crowding around the anode. If left unchecked, this crowding leads to lithium plating, resulting in significant cell degradation. 

Exponent solves this by combining their Battery Management System (10 times more accurate than the industry standard), Virtual Cell Model and Dynamic Charging Algorithms. This allows them to proactively sense Lithium crowding in real time and ensure each cell is rapidly charged without significant degradation. 

An independent testing laboratory validated this approach-TUV India (TUV Nord Group, Germany) and found only 13 per cent degradation after 3000 charging cycles of 15-minute rapid charging. 

15-minute rapid charging generates a ton of heat; 256 times more than the industry average of four-hour charging. The battery pack would overheat and switch off if this heat isn't extracted. 

Furthermore, in India, the ambient temperature is 40°C or higher and Li-ion cells have a far lower thermal sweet spot of 25-35°C. To solve this, we need advanced HVAC systems, which are both bulky and expensive. Additionally, this heat level is generated only when one rapidly charges an EV and does not drive it. 

Therefore, Exponent has built an advanced HVAC system that's "off-boarded" from the vehicle to its e^pump. While charging, the e^pump transfers refrigerated water through the e^plug to cool every Li-ion cell in the e^pack. 

This ensures the e^pack's temperature doesn't exceed 35°C in any ambient temperature condition. Furthermore, with the expensive system "off-boarded", EVs powered by Exponent are both affordable and lightweight. 

Speaking on the occasion, Arun Vinayak, CEO and co-founder of Exponent Energy said, "At Exponent, we're building the future of energy that combines cutting-edge engineering with real-world economics, and our off-board thermal management system is a testament to that belief. For everyone to go electric, consumers need EVs that charge faster, last longer, and cost less. Our unique two-sided approach to 15-minute rapid charging makes EVs last 3 times longer and cost 30% less than conventional EVs. We're excited to scale this across India, starting with Delhi-NCR, Mumbai, Hyderabad, Chennai and Ahmedabad!"

In the last three months, Exponent claims it has completed over 25,000 rapid charging sessions, covering over 10,00,000 kilometres with 200+ EVs powered by Exponent on the road in Bengaluru. Its 15-minute rapid charging also unlocks higher energy throughput, enabling the company to build the most profitable and scalable EV charging network. 

Their e^pump in Mahadevapura, Bengaluru, did a whooping 41 charging sessions in a single day, setting a new benchmark in the EV industry. The company is looking to expand its operations in five more cities - Delhi NCR, Mumbai, Hyderabad, Chennai and Ahmedabad by the end of FY '24 and is targeting to deploy 1,000 e^pumps and 25,000 EVs powered by Exponent by 2025.

In the past year, Exponent partnered with Altigreen, successfully launching the first EV powered by Exponent – the neEV Tez. Looking ahead, Exponent aims to deepen its presence in the 3-wheeler cargo and passenger vehicle market and explore new vehicle categories. 

The start-up is backed by key investors like Lightspeed India, YourNest VC, 3one4 Capital, AdvantEdge VC, Hero MotoCorp's Chairman and CEO, Dr. Pawan Munjal's family office, Motherson Group and has raised $18mn to date.