Most of today's electric vehicles (EVs) are powered by lithium-ion (Li-Ion) batteries—the same kind of batteries used in cell phones and laptop computers. Currently, most Li-Ion batteries used in EVs provide a driving range limited to 100 miles on a single charge and account for more than half of the total cost of the vehicle. To compete in the market with gasoline-based vehicles, EVs must cost less and drive farther. An EV that is cost-competitive with gasoline would require a battery with twice the energy storage of today's state-of-the-art Li-Ion battery at 30% of the cost.
Project Innovation + Advantages:
Sion Power is developing a lithium-sulfur (Li-S) battery, a potentially cost-effective alternative to the Li-Ion battery that could store 400% more energy per pound. All batteries have 3 key parts—a positive and negative electrode and an electrolyte—that exchange ions to store and release electricity. Using different materials for these components changes a battery's chemistry and its ability to power a vehicle. Traditional Li-S batteries experience adverse reactions between the electrolyte and lithium-based negative electrode that ultimately limit the battery to less than 50 charge cycles. Sion Power will sandwich the lithium- and sulfur-based electrode films around a separator that protects the negative electrode and increases the number of charges the battery can complete in its lifetime. The design could eventually allow for a battery with 400% greater storage capacity per pound than Li-Ion batteries and the ability to complete more than 500 recharge cycles.
If successful, Sion Power's project would encourage production of low-cost, high-energy, rechargeable Li-S batteries, contributing to the widespread adoption of EVs. Improving the number of recharge cycles limits battery replacements, saving drivers money.
Increased use of EVs would decrease U.S. dependence on foreign oil—the U.S. spends nearly $1billion per day on oil.
Greater use of EVs would reduce greenhouse gas emissions, 28% of which come from the transportation sector.
This battery would enable an EV to travel from Chicago to St. Louis (300 miles) on a single charge, for less than $10 on average.