Lithium-ion batteries are used in so many of the tech items we own today - phones, laptops, tablets, wireless headphones, e-bikes and scooters, cameras, portable chargers, and vapes. Every American household has roughly 40 lithium-ion batteries inside, according to the United Fire Authority.
When the battery starts discharging, the sulfur at the cathode starts losing electrons and forming sulfur tetrachloride (SCl 4), using chloride it stole from the electrolyte. As the electrons flow into the anode, they combine with the sodium, which plates onto the aluminum, forming a layer of sodium metal. Obviously, this wouldn't work with an aqueous electrolyte, given how powerfully sodium reacts with water.
Batteries in electric vehicles that regularly use 100-plus-kilowatts fast chargers degrade faster than those that rely primarily on slow charging, a new study suggests. Using fast chargers more frequently can cause some packs to lose nearly a quarter of their capacity in eight years, it claims. We've seen other studies suggest that fast charging has little impact on long-term battery health, so it's not a settled debate.
CATL says its new 5C batteries will retain 80% of their capacity after 1,400 charge-discharge cycles at 140F (60C). With a theoretical range of 372 miles (600 km) per cycle, that works out to a total of 522,000 miles (840,000 km) in what CATL describes as Dubai summer heat. At a milder ambient temperature of 68F (20C), which is closer to the ideal operating temperature for lithium-ion batteries,
Last year, the company's profit fell 45% compared with 2024, driven in large part by falling sales of its electric vehicles. Investors anticipated the decline in sales, but Tesla still beat Wall Street earnings and revenue estimates thanks to its energy storage business. Tesla deployed a record 46.7 gigawatt-hours of energy storage products in 2025, a 48% increase from last year, according to the company's official filings.