[MENTION=468175]Skipjacks[/MENTION], that's very useful. Thank you again!

I use cheapo 18650 cells in flashlights. I'm careful to stay present when charging the cells, and I got two of those supposedly fireproof charging bags just to be safe. All of this is more reason to buy from reputable companies.

My only Cygolite Hotshot is the older SL 50. It's been a mixed bag but I'd buy another newer, stronger Hotshot based on two years with this one.

For most of the first year the SL 50 worked as advertised. After about a year it would no longer hold a charge for as long as when new. Now at just shy of two years of use it needs to be recharged after every ride, or even after just sitting unused for a few days. It won't hold a charge for long.

I do wish there was more adjustability in brightness on the flashing modes. The SL 50 can be dimmed only in steady mode.

And a little better side visibility would be nice. The Hotshot's primary strength is a penetratingly intense light in a very narrow aperture. This effectively alerts tailgating drivers to move aside. Moving only a little to the side greatly reduces the laser beam brightness -- I've noticed this in group rides following other cyclists who use the Hotshots on the most annoying strobing modes. Just moving to the side reduces the intensity. But that's not necessarily a good thing in all circumstances. Hotshots are not particularly visible from the side, such as crossing an intersection perpendicular to oncoming traffic. (Nothing beats wheel mounted LEDs for side visibility.)

That's the closest I can come to a few complaints. All things considered it's been a good taillight.

On the plus side, it's very lightweight. I'm guessing that comes at the expense of using a smaller battery that's likely to fail sooner.

That light weight means it will always go with me even on the road bike when I'm shooting for personal best times. It doesn't weigh enough to matter.

Between the light weight and sturdy clip it has never fallen off, including the web strap on my Serfas saddle bags and homebrewed straps on the backs of my helmets. I've picked up many a stray taillight that's popped off another cyclist's bike in group rides, but the Hotshots seem to stay put. The taillights that pop off tend to be either the heavier models that use AAA or AA batteries, or wire clips. The replaceable battery models seem to generate enough momentum to require a much sturdier connection between light and mount. And those older style wire clips were useless.

The next best taillight I've used is the Blackburn 2'Fer. It's not quite as penetratingly bright as the Hotshots, but has better side visibility, is very lightweight with a sturdy clip, offers steady and flashing white and red modes all in a single unit, and the battery seems good as new after almost three years of use on nearly every ride.

Mine just stopped charging after just a little more than a year and VERY few uses/recharges. This seems to be a common problem with these, and all Cygolite advises is to send it in for a $6 (+$5 shipping and handling) battery replacement.

My 150 is 2 years old and I use it every day, no issues. Guess it's luck of the draw.

My wife is still using a Hotshot 2W that is about to turn 5. My semi-retired HotShot PRO is over 3 years old, and has, oh... 1,800 hours on it? I still reckon the HotShot series the best taillight for the money.

I've moved on to Varia, because you know. Gadgets!

I have no idea how old mine are and they are still working. OTOH, I think they are all the original hotshot, so it could be a bad data point
I'm a little disappointed in them because they just give up sometimes a lot sooner than I would expect. Probably because I can't be bothered to worry about charging them

Just thought I would add. I just moved and was going through boxes when, what should appear, but a maybe 9 -10 year-old Cygolite Milion. I think it was 360 lumens, which was bright at the time. Anyhow, I charged it up and guess what? I t works great. I don't need it, but it's not a half-bad smallish flashlight...

I’ve had two hotshot 100s. Lost the first one. If I were to buy a new one, I’d get the 150 or 200 because they charge with micro usb cables. The 100 used a mini usb, which is antiquated. It is the only thing I own that uses this cable and I have to hunt for it every time it needs a charge.

Cygolite may still help you. Get in touch with them.

However, this is why I carry a Blackburn 2'Fer light strapped to the seatpost on my night rides, despite using higher-end lights both front and rear. I've never had a tail light fail, but it's just a matter of time. And I definitely have had headlights fail a couple of times. The beauty of the 2'Fer is that although it's not a great headlight, it can be set to white or to red, flashing or not flashing. So if either my headlight or my tail light fails while I'm 12 miles from home at night, I can use it for either front or rear as needed.

Because 2'Fers can be obtained in two-packs, I put one as a backup light on both my road bike (the bike I put the most night miles on) and on my commuter/hybrid. If you're a night rider I think having a small, lightweight backup light is almost as useful as carrying a mini pump.

Dead battery
 

18 month old Cygolite 100 with a dead battery. I disassembled the light and tried a battery from one that was functioning. It worked fine. Put the Volt meter on the battery and observed 0.00 volts. then I attached my DuraTrax IntelliPeak ICE Charger (Model DTXP4170) on the battery. Set it up for Li Ion one cell 600mah and let it charge till nearly 500mah capacity. i reassembled the light and finished charging it with the USB interface.

it works fine now. Just curious how long it will last and why it was at 0.00 volts. By the way, I have never seen moisture in any of my rear Cygolites.

I would still send them a note via their on-website contact window. They will get back with you quickly. If you think they should just replace the whole light, just ask them to do it. I have never in 10 years and multiple purchases have them say no to a reasonable request.

They said they would replace a battery for me under warranty, but they replaced the whole light. They built a lot of good will that way.

I never bought the Hotshot, but typically Cygolite makes excellent products. I bought a Cygolite Metro 8 D cell 12 watt (which I upped to 14) halogen light way back in the late 80's, I used that light up until 2005 when I got my first LED light, and that thing still works today. That first LED light I bought was also a Cygolite called a MityCross 400 OSP, I was using that until I got a much smaller one for my helmet, it also still works, and the original battery holds a charge as if it was new.

So do I like Cygolites products? Yes I do. Are they the best made lights in the world? I have no idea but they lasted a very long time for me.

The only thing about ALL tail lights is the very small batteries they use, I had a Light & Motion tail light and the battery only lasted 4 years, but my other rechargeable front lights have lasted longer maybe due to the larger batteries? The other thing is that no matter what you buy you need to recharge it after EVERY ride, those batteries don't like to be drained to almost empty, they like to be recharged after every use no matter how little you used the light.

If you can afford it, the newer NiteRider tail light called the Omega 300, this beast puts out 300 lumens, I bought one because of its brightness, and that thing shows up extremely well even in direct broad daylight. It also has really good side visibility that the Hotshot is lacking. I can't answer the durability issue yet, I've only had it for a year, but so far it working just fine.

My Hotshot 150 Pro is still working great after a little over 3 years now. Haven't even noticed any loss in battery life.

My hotrod taillight doesn't run for three hours. I'm not sure when exactly it stops working. This is on a full charge. Do you think it's time for battery replacement? Or is this the expected performance?

Has anyone found a suitable battery yet? It bothers me to send it back to CL for them to just throw it away and send me a new one when all it takes is a battery.

I found one on aliexpress, search for item number 32965412711 (I'm not allowed to post links). Although it's in a hard case, it has the right dimensions (the original CL battery is 39 * 28 * 8mm according to my measurements, this one is 39.67 * 28 * 7.50) and it has three terminals with the middle one probably being the temperature sensor so the existing connector and wires could be soldered onto it as a drop-in replacement. And it is LiIon, not LiPo as it's supposed to go in some wireless headphones.

The battery is 7$ shipped for one or 11$ for 2.

Same here. Battery timestamp is 07/2017. Light doesn't last 3h on the breathing pattern with a full charge and dies without warning (just shuts off). When I power it back on, it even forgets what pattern and speed I had set which wasn't the case before when the light shut down from low battery.

Another data point. My Cygolite 150 is still kicking after over 2 1/2 years (bought it in August 2017).

NO tail light using those thin waffer Li-ion batteries will last longer than 5 years, and with a contest going on who can make the cheapest brightest light they take shortcuts in the quality of the battery. This is not Cygolite problem, this is industry wide problem; they can't make money selling a tail light that cost $40 and puts out 150 lumens but the darn thing lasts 15 years, so they shorten the battery life so you have to replace it more often. They do this for a lot of stuff not just lights.

Anyway Cygolite makes a good light, I have a couple of headlights, one is a Metro series from the early 90's that uses 8 D batteries and twin halogen bulbs that after a bulb swap mine put out 14 watts instead of 12.5 from the factory; this light still works I just don't use it any more since LED's came out and they're far cheaper to operate than to burn through 8 D bats. So I replaced the Metro with a Cygolite Mitycross 400 OSP, this one is rechargeable, I got it about 14 years ago, that battery is fine, but that battery is a separate bat and larger than than self contained bats/lights. Due to the size of that one I later got a Philips Saferide 80 that runs off of 4 AA rechargeables about 8 years ago, that one the original bats didn't last long but my replacement ones are doing fine.

The only thing I can tell you about any rechargeable battery is how long it lasts is how well you treat the battery. All you do is recharge your batteries after every use regardless how little it was used, if you wait and don't charge for several rides the deeper discharged cycles shorten the life expectancy of those batteries a lot. This is true for any rechargeable battery in any thing you use, even tools, this did not apply to the old NiCad bats.
Also if all possible only buy NiMh batteries made in JAPAN, this isn't always possible to know where a battery is made in a self contained object like a tail light, but if you have rechargeable batteries you use for other things and have a separate charger for them, like an AA battery make sure those are made in Japan, they will put out more power and last longer in both run time and life time. You can get an extremely good deal on Japanese made AA batteries directly from Ikea, do not go through Amazon for these because they'll charge you double! The brand that Ikea has is called LADDA, they have high current ones and regular ones,I got a several pairs of 2450 amp hr AA's for only $7 for a 4 pack. With AA and AAA you need a smart charge like the Ansmann Powerline 8 Battery recharger, or the La Crosse BC-1000 Alpha Power.

I think you are confusing Ni{Cd,Mh} and LiIon batteries. Ni{Cd,Mh} batteries are probably the worst offenders as far as memory effect is concerned and if you partially top these up often, the total capacity will degrade rapidly. On the other hand, LiIon are only affected by the number of cycles. So if you recharge a LiIon that is 90% full 10 times in a row, or one that is 0% full once (although technically LiIon can't be fully drained or they're done for); it will all amount to one cycle in either case. Topping up LiIon batteries after each use is not harmful to them.

LiIon batteries however lose about 20 or 25% of their capacity after a couple of years. That's a chemical process and it has nothing to do with how often or how little you recharge it. On top of that, their total capacity degrades after a few hundred cycles (consensus seems to be around 200 or 300 cycles)

What Cygolite (and others) could do, however, is to sell replacement batteries for a reasonable price. It is very easy to swap the battery in the Hotshots, provided you can find a suitable replacement: 3 screws to remove and a connector to undo. But instead Cygolite has no option to buy a standalone battery for 10 or 15$ (the most it should cost IMO considering how small it is). No, you have to send the light to get a battery "replacement" which is actually Cygolite tossing your light in the trash and sending you a new one when all it needed was a fresh battery.

The above is incorrect. In fact, NiCad batteries DO suffer from voltage depression, but it's reversible. Li-Ion batteries, as used in Cygolite taillights, can be charged at any point with no effect on battery charge or longevity.

Above is correct.

Tried to find the oldest photo I have for my Hotshot Pro80; to remember how old it is.
This photo was taken on DEC 2015. Still working fine up to this day. :)
https://live.staticflickr.com/5754/2...7c800541d2.jpgLights on my Brompton by 1nterceptor, on Flickr

I have a Cygolite Hotshot– High Power 2 Watt that I got from Amazon Sept 2015 and it works fine.

I have a Cygolite Hotshot 100 that I purchased from Amazon almost two months ago. It's now showing signs of failure as evident on the last two rides. It will run approx.10 minutes on daylight mode then shuts down inexplicably. I've charged it at home and the light blinks as it should but turns solid after only 10 minutes signifying a full charge. Go figure. Fortunately, I’m still eligible to return it by May 31 but now am now unsure if I should submit a claim to replace it or request a full refund.

Might be easier to go through Amazon if possible...But if not, this thread suggests that Cygolite will take care of it. That's a bit of a hassle, and shouldn't happen on a two-month old light. Perhaps they would ship you a new one without returning the old one? At least you could avoid a trip to the Post Office.