A writer named Hello decided her old rechargeable bike lights were worth fixing rather than replacing. The problem was simple: after a full charge, the lights lasted five minutes. The solution involved cutting open silicone, desoldering a battery she couldn’t identify, and asking an AI what the part was. It worked.
The Problem
Hello bought her rechargeable bike lights ten years ago. She hadn’t tried them in a long time. When she plugged them in to recharge, the lights only worked for maybe five minutes before turning off. She suspected the battery was dead, but she doesn’t know much about electronics.
She went to a local queer makerspace where she’s a member. The space gave her access to tools she wouldn’t otherwise have, and the chance to get help from others.
Cutting Open the Silicone
The bike light felt like it was made of silicone. Hello cut open the silicone in a haphazard way along something that vaguely looked like a seam. She ripped some silicone in the process, making a mess. But she got the circuit board out.
She doesn’t know the model number of the bike lights. There’s a photo of them at the end of the post.
Removing the Screws
There were some screws holding things together. Hello removed them carefully, trying to lose as few as possible. She probably put the screws in a bag or something.
Getting the Circuit Board Out
The circuit board showed where the battery was attached. Hello thinks it’s left of RI3 and above Q2. The battery itself was marked with numbers she couldn’t read.
Desoldering the Battery
Hello had never desoldered anything before. She found an iFixit guide and followed the steps:
- Use a desoldering pump to remove most of the solder
- Pull the battery apart once most of the solder is gone
- Avoid overheating the battery by taking breaks to let it cool down
- Leave the welded attachment on the top of the battery — the replacement comes with it
Lee and Lauria offered advice along the way. Hello is not very good with a soldering iron, so it took a while.
Identifying the Battery
The battery was marked with numbers that didn’t mean anything to her. It said something like “3” and “LI???77.” There was a piece of metal welded to the top that seemed impossible to remove.
She asked an LLM. The response was “LIR2477,” which matched her battery exactly when she looked it up. She figured that was plausible. She would be interested to learn non-LLM ways to figure this out.
Lauria showed her how to use DigiKey’s search. That was cool, but DigiKey didn’t have that part.
Buying the Parts
Hello went to AliExpress and ordered two batteries — one for each bike light — plus some silicone glue to put things back together. The batteries were $3 each. The glue was $8. The parts took two weeks to arrive.
Soldering the New Batteries
Once the parts arrived, Hello went back to the makerspace. She soldered in the new batteries, put the screws back in, and used the glue to reassemble the lights. The screws were very small and hard to hold, so she dropped some on the ground and couldn’t find them. She used fewer screws and hoped for the best.
She clamped the parts together halfheartedly while the glue dried. Then she waited for the glue to cure at home.
The Old Batteries
Hello took the old batteries to somewhere nearby that accepts old batteries.
It Works
The lights work. She has used them to bike at night. She hasn’t needed to recharge them yet, but tragically she had to order a new Mini USB cable because she got rid of all her Mini USB cables. She’s still waiting for that.
She didn’t glue carefully. The light didn’t really go back together that well. But she hopes it’ll be good enough.
The Cost
It cost about $20 CAD to buy the parts. Whether the repair holds up, she’ll try to update this post in the future.
The Numbers
| Step | Action |
|---|---|
| 1 | Cut open the silicone |
| 2 | Remove the screws |
| 3 | Get the circuit board out |
| 4 | Desolder the battery |
| 5 | Identify the battery |
| 6 | Buy the battery and glue |
| 7 | Solder the new battery and glue it back |
| Part | Cost |
|---|---|
| Two batteries | $3 each |
| Silicone glue | $8 |
| Total | About $20 CAD |
The Outcome
Hello’s repair is a triumph of curiosity over caution. She cut open a product she barely understood, followed an iFixit guide she found and read, and asked an AI for help identifying a part she couldn’t read. The project shows what a makerspace can do. Hello got help from friends and access to tools she wouldn’t have had at home. She could have thrown the lights away and bought new ones. Instead she fixed them herself, for about $20.
The repair isn’t perfect. The glue is sloppy. Some screws are missing. But the lights work. They’ve been used at night. They haven’t died yet.
This is the part worth watching. A repair that costs $20 and works is a good outcome. The time spent was real, but the result was functional.
The story is a reminder that repair is often uncertain. Hello knew almost nothing about electronics. She followed a guide. She asked for help. She got the job done.
Source material: “Replacing the old battery on rechargeable bike lights,” jvns.ca.
Get the Notebook.
The day's best stories and every fresh verdict, in plain English, in your inbox by seven. One email a day, no more.