Replacing the old battery on rechargeable bike lights
Julia Evans successfully revived ten-year-old rechargeable bike lights by slicing open the silicone casing and soldering in new $3 batteries.
read it It is a charming, lightweight build log that encourages right-to-repair and breathes life into dead electronics.
summary
Julia Evans shares a practical build log detailing how she repaired a pair of decade-old rechargeable bike lights that no longer held a charge. Utilizing a community makerspace, she cut open the silicone housing, desoldered the dead coin cell, and used an LLM to identify the LIR2477 replacement part. After installing new cells ordered online, the lights were successfully restored for about $20 CAD total. The post underscores how minor DIY efforts can keep functional hardware out of landfills.
key points
- The dead batteries were LIR2477 coin cells identified using an LLM, though physical measurement with calipers provides a manual alternative.
- The total cost for repairing two lights was roughly $20 CAD for replacement batteries and silicone glue.
- Commenters note that many commercial bike lights frustratingly use soldered or proprietary batteries rather than user-replaceable options.
who should read it
Hobbyists, engineers, and right-to-repair advocates looking for inspiration to fix old consumer electronics.
discussion warm
consensus
Commenters enthusiastically validate the repair project while lamenting that consumer bike lights are designed with non-replaceable, soldered batteries that force premature obsolescence.
pushback
A few commenters warn about the safety risks of sourcing cheap lithium batteries from AliExpress and potential sizing discrepancies.
For removing soldered-in batteries like this - I do it on synthesizers a lot - instead of risking heating it up too much just cut the legs off and pick them out individually.
Same for any multi-legged part with soldered-down mounting tabs like pots, chop 'em up and remove 'em a leg at a time. You'll put far less heat into the PCB, drastically reducing the risk of damaging the pads.
When you come to solder the new battery in, you'll have trouble getting the solder to stick. Get a blob of blutac, stick the battery to your bench, tin the legs very lightly, and let it cool for a few minutes …
Provides a superior, PCB-safe technique for removing soldered batteries by clipping leads rather than risking heat damage with a desoldering pump.
Generated by an LLM from the article and thread. Check the sources before relying on it.