Everyone wants a battery that charges in minutes. The cell does not cooperate easily. Charging means pushing lithium ions from the cathode into the anode, where they should slot neatly into the graphite. Push too fast and the ions cannot insert quickly enough — so they pile up and plate as metallic lithium on the anode surface instead. That plated lithium is mostly lost capacity, and at worst it grows into dendrites that can short the cell.The 2023 grants are direct assaults on this limit. Southwest Research Institute's US11557797B2 claims control of lithium plating during charging — naming the enemy outright. Its US11646597B2 claims fast charging using pulse-width-modulated charging combined with cooling, pulsing the current and managing heat to push more energy in without triggering plating. StoreDot's US11560062B2 claims software management of EV battery modules, the control-layer approach to the same problem.The mechanism behind the fix is about not exceeding the cell's ability to absorb lithium at any given moment. That ability depends on temperature, state of charge and the cell's age — a cold cell or a nearly full cell plates much more easily. A smart fast charger therefore varies the current continuously: hard when the cell can take it, gentle when it cannot.Does it pencil? Fast charging sells cars and reduces the practical penalty of an EV, so there is real revenue behind solving it. But every fast charge that plates lithium shortens pack life, and pack replacement is the single most expensive event in a battery's economics. The value of these patents is in getting the speed without paying for it in cycle life later.Temperature is the recurring co-star. Southwest's pulse-and-cool approach is explicit about it, but all serious fast-charge methods manage heat, because the same cooling that protects the cell also widens the window in which it can safely accept current. Fast charging and thermal management are two halves of one problem.For readers, the practical signal is in the charge curve. A cell that holds a high charge rate across a wide state-of-charge band, without overheating, is one whose maker has solved more of the plating problem. A charge that slows dramatically after 50% is the cell protecting itself — honest engineering, but a sign the easy speed has limits.
“A method of controlling the charge current during charging of a lithium-ion battery. A battery charging controller is based on a Kalman filter, which uses estimated battery states to generate a feedback metric to continually adjust a battery cell model.”— U.S. Patent No. 11,557,797 source