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Replacing the old battery on rechargeable bike lights

52 pointsby 2h agojvns.ca
17 comments
1h agoHN ↗

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!

1h agoHN ↗

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.

1h agoHN ↗

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.

54m agoHN ↗

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.

9m agoHN ↗

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

1h agoHN ↗

Love this. I have a pile of nice Cygolites (both front and tail) that my whole family uses that are maybe 8 or 9 years old. Their capacities have largely dropped to the point that I need to charge them every ride or two. Maybe get about 90 minutes of use, down from 3-4 hours previously.

They're not user-serviceable by design but I've been pondering cracking them open and having a go at swapping the batteries. This post may inspire me.

I've got a pile of new 18650s lying around and hopefully the front lights use those!

48m agoHN ↗

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.

29m agoHN ↗

The best motorcycle sunglasses i every bought were mec, from the vancouver store in around 2005. Flat sided (for helmets) with interchangable lenses, and seriously dark lenses too. But when I walked in, in full sportbike leathers, i got more than a few dirty looks.

12m agoHN ↗

Did we not just see the battery replaced? ;)

44m agoHN ↗

I don’t know what it is with Julia’s writing but it always makes me happy. It reminded me of replacing the soldered battery in Super Metroid so I could save my progress again. As a cheapskate I used a regular battery and connected the wires mechanically.

43m agoHN ↗

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.

3m agoHN ↗

The chemistry set the voltage and the voltage and the size set the capacity. Everything else equal, larger capacity is often compatible with a smaller capacity battery in a device because the charge current will be lower in relation to the capacity.

43m agoHN ↗

I know it's slightly offtopic, but the brand I am using - ExposureLights - offers a battery diagnosis/replacement service for their bicycle lights.

Those are on the expensive side, but still, most brands would rather sell you a new one.

22m agoHN ↗

Love to see MEC gear - but I wish it were more repair friendly!