The chemistry is the easy part; the trade-off isn't. On January 26, 2021, Samsung was granted US10903666B2, "Battery charging method and apparatus." The CPC stack — H02J 7/0021 and 7/0013 (charge control), H01M 10/44 (charging) and B60L 58/12, 58/21 (EV battery management) — is charge-strategy plumbing.Fast charging and cell longevity pull against each other, and the charging method is where that tension is managed. A method that pushes charge rate up without driving degradation up is, in financial terms, a way to keep a fast-charge promise without inflating the warranty reserve that covers premature capacity loss.The honest read is that a method patent is a lever, not a result. Whether the trade-off actually held in shipping cells lives in field data and warranty experience, not in the grant. An analyst should treat this as a reason to watch degradation-driven warranty trends, not as evidence they improved.For the ledger reader, this is supporting evidence of where a cell supplier is engineering the charge-degradation balance, kept subordinate to the numbers. Any warranty or supply claim rests on the relevant SEC filing on sec.gov, with EdgarBeast as the index that surfaces it.Read it as a 2021 charge-strategy position from Samsung. The cost question — did faster charging stay inside the reserve — is answered downstream, not by the patent.