Development of High Energy Lithium-Sulfur Cells for Electric Vehicle Applications
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.