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!
Well done!
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
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.
On so many occasions I would get blinded by overly bright lights of an incoming cyclist during late evening ride.
It's probably this way because companies design products to cater to their customers, who would likely prefer a Damn Bright Light to feel like they got their money's worth.
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.
So if you are blinded by an incoming cyclist this is not legal... of course enforcement is another matter.
I wonder how many people just chucked the unit when the battery wore out.
Those are on the expensive side, but still, most brands would rather sell you a new one.
These lights would have predated the private equity era but I'm guessing sourcing options were somewhat more limited back in 2016.
They're just generic DC 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 out of it.
You'll spend more time futzing with one of or dealing with weather-related failures that you would have saved more time charging a pile of batteries before every ride.
https://www.sjscycles.co.uk/hubs-front/shimano-nexus-dhc3000...
Dynohub history rabbit hole for those interested:
No, it's about a tenth of that, light included.
I explored dynohubs in the past, but LEDs and LiPo batteries have really narrowed the gap. In my garage, I've got a super long USB cable that we all use for charging our lights. I've used cheap lights from AliExpress, and they are actually quite durable.