In the Netherlands many people use these kinds of detachable bike lights. I've never came across soldered batteries in the dozen or so I've replaced batteries for. Not always cheaper, but just tossing the whole thing seems like such a waste.

Well done!

There are also dynamo powered LED lights which only provide light while riding the bike, and about a minute afterwards (I assume from an internal capacitor). They are not detachable but why would that be necessary? From what I can tell they also don't require regular replacement.

These are fine for bike commuters, and I’ve had them before. But they are in general not fine for recreational bicyclists; these people would gladly pay a hundred dollars for a new tire to shave off three watts and are not about to add any unnecessary human-powered accessories.

An exception is bikepackers, who may prize reliability and runtime over brightness and weight. But then the dynamo we're talking about is $200-$400 and that's not including the light.

An exception is bikepackers, who may prize reliability and runtime over brightness and weight. But then the dynamo we're talking about is $200-$400 and that's not including the light.

No, it's about a tenth of that, light included.

A reliable dynamo hub setup can be very cool for the right situation, but the up front investment to rebuild your wheel around a dynamo hub is expensive. The power output is also on the low side compared to the light output you can get from the battery units.

Not having to charge anything or worry about batteries running out in the dark is a real benefit.

It's all on the very opposite end of the cost spectrum than the cheap bike light in this post though

The old-school dynamos cost 10-20 bucks: https://axabikesecurity.com/product/axa-8201-right/

They're just generic AC motors held against the rim, as simple and cheap as it gets. Nowadays I'd add a basic voltage regulation circuitry to get a stable 5V DC out of it.

Talk about burying the lead. This was a MEC bike light. It should have a replacable battery!

https://www.mec.ca/en/explore/sustainability-innovation

Ah, memories. I miss the old MEC, before they overextended on real estate and had to sell the farm to private equity. I have a pile of MEC branded gear I'm still happily using 20 years on. I have some restrained hopes for the new ownership group to bring it back, but I'll always miss the co-op.

These lights would have predated the private equity era but I'm guessing sourcing options were somewhat more limited back in 2016.

I wouldn't worry about matching the exact model number of the battery. Instead, it's more important to get roughly the same chemistry and a capacity equal or maybe a touch greater (if technology improved in the last 10 years, capacity could be greater with modern parts).

Specific batteries go in and out of production. But as long as it's the same CHEMISTRY, voltage, and capacity, it's likely compatible. Chemistry tends to set the voltage, size sets the capacity.

Charge/discharge controllers and algorithms are based on these three bits of info.

In some cases, some chemistries are actually compatible with other chemistries. NiHM cells are largely backwards compatible with Ni-Cd chargers (but not vice versa). It's not good for the NiHM but they will actually take the charge.

I recently had an even easier time changing the rechargeable battery in some mini Christmas lights. The unit was a solar panel in a box held by 4 screws. Took them out, and it was a regular AA nimh just slotted in there. Changed it out and the thing worked again.

I wonder how many people just chucked the unit when the battery wore out.

On the subject of bike lights. Most of the current lights appear to use some LEDs which makes sense, of course. However the brightness of output light looks like completely unregulated.

On so many occasions I would get blinded by overly bright lights of an incoming cyclist during late evening ride.

It's not a brightness thing, after all car headlights are probably 1000x brighter than anything you may have on your bike.

It's because 99% of bike lights are basically just flashlights, spraying light everywhere. The solution is the same as for cars — lights with horizontal cut-offs.

If it killed the first battery, won't it just do it again to the new one?

If anybody's interested in what the meta is for buying bicycle lights:

  1. Reflectors are the best for baseline visibility, they cost nothing and are reliable.

  2. The tail light is the important one.

    a) Try to find ones with a pulsating mode, blinding other road users by shining bright rapidly blinking lights into their eyes is not good, actually.

    b) If you've got the money, consider a radar instead.

  3. For the front, decide if you *need* illumination strong enough for you to see where you're going in darkness, or if you can get away with just being seen by others.

    a) For the former, make sure you get a front light that has a beam cutoff, preferably a lens-based solution. Then of course, install the light with a proper downwards angle, otherwise there's no point to the cutoff.

  4. Side visibility is important, this is usually accomplished by some see-through parts at the business end of the light.

  5. DO NOT use blinking modes at night. Blinking is for daytime, use only constant or at most, pulsating modes at night.

  6. BTW, the 2nd most important piece of equipment after your tail light is a mirror (>=2inch diameter).

Some recommendations:

• If biking casually or without a need for strong front light, honestly just get the cheapest lights you can get + some reflectors. Having any light at all gets you 99% there.

• Magicshine lights in general, I myself have the EVO 1300 for front and the SeeMee 300 for back. Proper lensed beam cutoff for the front, pulsing modes for the back, and good side visibility for both.

• Bontrager Flare RT for the back — small but powerful thanks to its focused beam. They also seem to have a front positional version but I haven't tried it.