The author found that her ten‑year‑old rechargeable bike lights would only stay illuminated for about five minutes after a full charge, leading her to suspect that the internal coin‑cell batteries had degraded and wondering whether she could replace them rather than throw the lights away.
She opened the silicone casing with a blade, removed the screws holding the circuit board, and took the board out to expose the original battery. By looking at the markings on the cell, using an LLM which suggested the part number LIR2477, and checking DigiKey’s inventory (though the exact part was not stocked), she determined the replacement needed. She ordered two LIR2477 batteries and some silicone glue from AliExpress for roughly twenty Canadian dollars, then desoldered the old cells with a desoldering pump while managing temperature, soldered in the new batteries, reassembled the light with the glue, and let the adhesive cure for twenty‑four hours.
After the repair the lights functioned for night‑time riding, but she has not yet measured how long the new batteries will hold a charge and is still waiting for a mini‑USB cable to recharge them, leaving the long‑term durability of the repair uncertain. She notes that the fix cost about $20 CAD, warns that batteries from AliExpress may not match their labeled specifications, and points out that her account contains no safety advice because she lacks electronics expertise, suggesting that readers exercise caution and consult proper guidelines when attempting similar repairs.
Image shows the bike light functioning after the battery swap, confirming the repair's success as described in the article.