It's weird that rechargeable bike lights almost universally use soldered batteries. Conventional flashlights with onboard charging often use standardized cylindrical Li-ion cells that are field-replaceable by unscrewing the tailcap. They're usually 14500, 18350, 18650, or 21700 size, sometimes with a protection circuit stuck on the end (making it semi-standard, but easier to handle safely).
The light in the link uses an absolutely tiny 0.5Wh battery, which strikes me as insufficient for cycling. I use a light with a 21700 cell (20Wh).
It’s more of a “be seen” light rather than one that lights the way ahead.
My jurisdiction requires a solid white light facing forward at night, but you can have a flasher in addition to that (cuz drivers still won’t see you with a solid light…).
Also a good backup it your main light does to stay legal.
I'd love to see an actual standard for user replaceable batteries. Raw lithium cells are just far too dangerous considering they can explode from being short circuited. So products have the choice of either non replaceable, or proprietary packs.
Given the EU is mandating replaceable batteries very soon we might see some momentum on this.
The premium flashlight market has solved this with semistandard protected button-top cells.
These consist of a standard cell with a protection board stuck on the end, and usually a smaller raised positive terminal. This adds 3-5mm to the length, and temporarily breaks the circuit in the event of over-voltage, under-voltage, or over-current/short. There's no written standard, but most brands are making pretty much the same thing, and they almost always interchange. Safety does not require it to be proprietary.
Here's an example from a flashlight manufacturer: <a href="https://www.skilhunt.com/product/bl-135-3500mah-18650-protected-battery/" rel="nofollow">https://www.skilhunt.com/product/bl-135-3500mah-18650-protec...
Here's an example from a third-party battery distributor: <a href="https://illumn.com/18650-keeppower-p1840c-4000mah-protected-button-top.html" rel="nofollow">https://illumn.com/18650-keeppower-p1840c-4000mah-protected-...
Zak · · focus · HN ↗
The light in the link uses an absolutely tiny 0.5Wh battery, which strikes me as insufficient for cycling. I use a light with a 21700 cell (20Wh).
Scoundreller · · focus · HN ↗
My jurisdiction requires a solid white light facing forward at night, but you can have a flasher in addition to that (cuz drivers still won’t see you with a solid light…).
Also a good backup it your main light does to stay legal.
Gigachad · · focus · HN ↗
Given the EU is mandating replaceable batteries very soon we might see some momentum on this.
Zak · · focus · HN ↗
These consist of a standard cell with a protection board stuck on the end, and usually a smaller raised positive terminal. This adds 3-5mm to the length, and temporarily breaks the circuit in the event of over-voltage, under-voltage, or over-current/short. There's no written standard, but most brands are making pretty much the same thing, and they almost always interchange. Safety does not require it to be proprietary.
Here's an example from a flashlight manufacturer: <a href="https://www.skilhunt.com/product/bl-135-3500mah-18650-protected-battery/" rel="nofollow">https://www.skilhunt.com/product/bl-135-3500mah-18650-protec...
Here's an example from a third-party battery distributor: <a href="https://illumn.com/18650-keeppower-p1840c-4000mah-protected-button-top.html" rel="nofollow">https://illumn.com/18650-keeppower-p1840c-4000mah-protected-...