On principle I believe batteries should be replaceable, regardless of their chemistry. Throwing away an otherwise working device because it was made with a non-replaceable rechargeable battery is wasteful. That said, the lithium chemistry rechargeable batteries have been improving over time and product designers have been making lighter and brighter lithium chemistry powered lighting products, My main ride has a dynohub and powered lighting front and rear so no real batteries there other than my wrist worn Garmin Foretrex 601, which I use mostly with rechargeable AAA batteries or disposable (and increasingly expensive) Energizer lithium AAA batteries. On other bikes, we use a collection of Planet Bike Superflash Turbo and Portland Design Works rear blinking lights with the aforementioned rechargeable and disposable batteries. We do have some rechargeable lights around but they don't see much use.

I would like to see a device that could use multiple types of batteries and be able to charge NiMH or LIthium rechargeables by connecting a USB-C power cable. Unfortunately, while technnically possible, without proprietary cell packaging so the device would be able to detect what type of battery chemistry was installed, such a device would rely on the user to make sure they didn't try to charge nonrechargeable cells or use the wrong setting for a particular cell chemistry, which in turn might increase the risk of fire or explosion. That's why it is uncommon to see devices that can use either replaceable disposable or rechargeable batteries have any ability to charge batteries in the device.

I think it is simpler. For example phones, it is very hard to find a phone these days that has a user replaceable battery. Phone companies have figured out that if your battery goes bad in three years, instead of paying a shop to replace the battery you are more likely to replace the phone. And they hope that you will be a repeat (profitable) customer.

When I go backpacking, canoeing or kayaking, I really like having the ability to just swap phone batteries when my battery goes down. There is enough room under my phone inside this weatherproof case to hold two spare phone batteries which are user replaceable.

https://cimg4.ibsrv.net/gimg/bikefor...0889990ce2.jpg

I also bring spare batteries for my camera on such trips.

But bike touring, I can charge up the batteries from my dynohub pass through cache battery, so that is less of an issue. Thus, I bring fewer spares on such trips.

Certainly, planned obsolescence is one of the factors in the lack of equipment with replaceable batteries. There are imperfect workarounds such as how some people use external battery packs. My comment was about wanting lights and other items powered by batteries to be able to accommodate different battery chemistries and the ability to charge or not charge the installed battery chemistry. For example, if a device used AAA batteries, you could install AAA NiMH batteries and use a charging cable to charge the installed cells. If you instead installed non rechargeable alkaline AAA batteries, the charging system would not attempt to charge them as that could cause accelerated leakage or other damage. I want flexibility of power sources and useful longevity, which the marketplace doesn't readily supply for a variety of reasons.

Phones are a special use case where the tight integration of the non replaceable battery has become ingrained in the design and engineering of virtually all smartphones, hence very few current model phones have replaceable battery packs. Further, those that do have replaceable battery packs cannot accomodate difference battery chemistries such as switching from Lithium to NiMH as an example.

Finally, while I usually carry a mobile phone, I relish leaving my phone behind or turned off and being immune to interruptions from a mobile device on my rides.

TOTALLY AGREE! This sort of nonsense of throwing away a perfectly good light that probably has at least another 80,000 hours of light left on the LED from the original 100,000 hour usage they average, just because the battery failed charge after 3 to 6 years. They do the same thing now with cell phones, they now are gluing the battery in place so that the user can't replace the battery when it will no longer hold a charge! Phone is perfectly fine but, nope, gotta go and throw it away and spend a bunch of money for new one. iPhone is even putting certain upgrades in the phone that as it ages they make some sort of function on the phone inoperative after an upgrade, and they slowly do this till you decide to get a new phone. That sort of stuff should be against the law, if a cell phone only cost $50 then who cares? but they don't.

All this waste means they have to make new stuff, which means there are factories spilling out climate change gases, which tells me that climate change being caused by humans is a huge lie, otherwise they would be working diligently to make things last as long as possible, and be able to repair stuff, change batteries etc to prolong the life of the object. Of course all this remaking of stuff means using up valuable natural resources as well. I have a friend who has a International refrigerator made sometime in the 40's that is still running! They've been using ever since they inherited from her mom who had also never stopped using it; never any repairs just a couple of seals. I know we can make stuff to last a very long time, but they don't want to because of corporate stock holders need their shares to go up.

It would be nothing to do, and cost nothing extra, to make a light that the user could open it up and replace the battery when they no longer will take a charge. Then the company who made the light would just make and sell you a battery...as long as they don't get stupid and charge as much, or even near as much as a new light! Or make the battery so it only will recharge for a couple of years!

My Garmin 64 GPS uses two AA batteries, disposable or NiMH. It can also run on a proprietary Garmin battery pack. And if you use that Garmin battery pack (that consists of two AA NiMH batteries), you can charge the battery pack with a USB cable (mini, not micro USB). Or, you could do what I did, use a small piece of metal held in with tape, the two NiMH batteries I put in push on that metal piece which pushes down on a button to fool the GPS into thinking that the proprietary battery pack is installed. I use that GPS for bike touring, when I am down to one bar on the battery scale, I plug it into my pass through cache battery pack that is charged by the dynohub for maybe an hour and then unplug it. But, the way I do that if you wanted to use disposables, you would have to remove that little piece of tape holding that metal on the button.

Most months my cell phone is not used, I only have it for travel. I give out my cell number to almost nobody, I do not want them to call or text me, and then they get pissed when I do not respond. If you give people your number, they assume that they can call you and actually get you. I only give out my land line number.

But I carry the phone on the bike on longer rides in case for some reason I need help. When I travel, I usually am trying to get a forecast a couple times a day so I can plan what I want to do and when. And if I am on a bike tour, backpacking or canoe trip my sister will panic if she does not hear from me every 2 or 3 days, so I need to make some calls or send some e-mails when I travel so the family does not worry. That said, the phone is always either off or in airplane mode if I am not using it.

There are some still around (Blackburn, CatEye, others) and even some newer designs. The PlanetBike Superflash 65 is mfr rated @ 65 lumen flash (the regular Superflash is mfr rated @ 7 lumen), 30 lumen steady.

In comparison, the CatEye ViZ 450 lithium rechargeable is mfr rated @ 40 lumen flash, 40 lumen constant and a retina-searing 450 lumen 'Daytime Hyperflash'.