Cheers, I'll try and be carefrul then.

Yay, Cherrybomb 100 arrived this morning.

I'm quite liking it so far:
..
So I put my Bertin frame on a garden table and strapped on the Cherrybomb 100 (top) and the Sigma Buster RL 150 (bottom, 150 lumens supposedly).
Here's what it looks like from 10 feet (80mm lens)
..
And here's the view from 30 feet:.
Edit: That's using the supplied alkaline 1.5v batteries.
Edit2: Sigma on day flash, Cherrybomb on fast flash. So both on "day flash" equivalent.


BTW. Probably don't buy batteries from Aliexpress.
12800 mWh https://www.aliexpress.com/item/1005008490712108.html
Although they do list Xtar which are probably ok but the same price as UK.

FYI just found out Kirkland batteries are from Duracell via Costco

The Photoolex 1300 mWh batteries also have small print on them saying
..
Being generous that might be a guaranteed minimum, or maybe "1300 mWh" is a lie.
I've set the Cherrybomb on full beam with a freshly charged set, in theory it should last around 49h if it's 1300mWh.

I assume if a battery gives me at least 90 percent of rated capacity, that it good enough, that was my assumption before I read this. So I find it interesting that the rating on the battery is exactly 90 percent of the rating on the package. I do not recall ever seeing a rated number on the package that differs from the printing on the item inside the package.

If the hour run time rating is based on declining voltage and possibly declining amperage as the battery runs down, the light gets dimmer over time but, those dim hours that consumed less energy are counted too. The Li Ion AAA batteries put out a constant 1.5 volts and the light should stay bright the whole time until the battery is exhausted, thus no dim hours, thus runtime might be shorter than the math suggests.

I have been using the Lezyne ZECTO DRIVE MAX 400+ REAR. This thing is a killer taillight - 400 lumens that runs at 16 hours - enough for a whole day on the bike + a little extra.
Give it a look.. They have a 200 lumen version for a little less money as well.

https://ride.lezyne.com/collections/led-rear-bike-lights/products/zecto-drive-max-400-plus-rear

My Cygolite Hypershot 350 is rated at 350 lumens. I've had people complain it's too bright. I haven't figured out how to dim it. I'm in NYC, a very dense place, i.e. no country roads, so it is brighter than I need.

I haven't figured out how long the battery lasts but it seems to be more than three hours.

Cheers, that looks quite interesting. I've put it on my list.

I've been testing batteries and the Cherrybomb 100 specs are wildly optimistic.
Best I've got so far is some Eneloop 750mAh running for 22 hours on Day Flash (still running, just), the spec says 96 hours.

Edit: 23.5 hours from an Eneloop 750mAh.

So I've ordered some other batteries to try
..
The Xtar 1620 mWh have long delivery times so testing the 1200 instead.

That does get good reviews: https://www.paddleroundthepier.com/best-bike-lights/
And adjustable flash speed sounds great.

Most bike lights have multiple modes but if you angle the light slightly up - you will blind other cyclists. It should be parallel or slightly down. I ride solo later at night - so full power is my default.

when I have group night rides - I always look for the retina burners and tell them to put in a lower mode. There is safety in numbers at night.

That was quite tedious, but now the results are in ..
Initially I was testing using "Steady High" to speed it up, but the results looked funny so I switched to my intended use - "Fast Flash" which is the daytime flash setting.

Edit: Time 'h' is time in hours until the light stops flashing.


My observations:
..
So my cunning plan is:
..
That gives me 24 hours runtime and 1.2 hours of full beam on the front lamp in emergencies.


BTW. There's an active r e d d i t group for batteries at https://www. re**it .com/r/batteries/

Update:
Front light is saying recharge me after 7 outings which is around 21 hours.
I'll take that as a win

Sorry for being off topic here, responding to previous post.

I added underline, below:

I am not a battery scientist, so this is only a guess on my part. I said this in a previous post in this thread:
..
Perhaps I was not clear, what I am saying is that at 1.5 volts, I think the light is brighter and drains the Li Ion 1.5v battery faster. That is why I like those batteries in my kitchen weight scale, the NiMH batteries at lower voltage have a very dim backlight, but last a long time. But I want a brighter backlight, even though it uses more energy in that particular device.

I am surprised that your Li Ion constant voltage batteries ended at 1.23v if I am reading your notes in the table right. The ones I have stay full power and go to nothing when they are empty.

For bike touring where I am tenting, I do not have the luxury of plugging into an outlet daily, I have to be very frugal with my power usage. My last three bike tours, I was self sufficient on electricity with only a dynohub and a dyno powered USB charger to charge a powerbank for several weeks.

I tried the Li Ion AA batteries in my GPS, It is not a cycling GPS model, the Garmin 62/64 series of GPS units use AA batteries. And the run times suggested that the Li Ion should give me good service. In March 2025 I did some measurements with a Garmin 64ST, backlight off but screen constantly on:
.

• GPS consumes 0.525 watts with USB cable, no batteries.
• Li Ion AA batteries give me an hour of run time for 0.46 watt hours to recharge the batteries after use.
• Ikea Ladda 2450 AA NiMH batteries, recharged in a Eneloop two cell charger (powered by USB cable) consumed 0.58 watt hours to recharge the batteries for every hour of GPS runtime.

.
Thus, the Li Ion batteries should require less total energy than the NiMH batteries. I think the recharging process for NiMH batteries consumes more energy than it does for Li Ion.

On a bike tour I usually charge my AA NiMH batteries that I use for the GPS in my GPS while rolling instead of using the charger on the batteries later. (This takes a work around to use the built in charger in the Garmin on NiMH batteries, I have to fool the GPS to think the Garmin proprietary battery pack is installed.) But if I run the Li Ion AA batteries in the GPS I will have to pull the batteries out to charge them. Thus, would frequently be swapping batteries if I instead use the Li Ion batteries for touring in my GPS. So, not sure which batteries I want to use on my next tour, I plan to bring both kinds of batteries.

My headlamp (for my head), I will use NiMH batteries, they do not suddenly quit when they run down, I want adequate warning when my battery needs to be changed. I am inclined to use NiMH batteries in my taillights that use AAA batteries for the same reason.

Thank you very much for posting your times and observations. As far as I know, you and I are the only ones on this forum that have tried the constant 1.5v AAA Li Ion rechargeable batteries.

Thanks to both of you for all your knowledge and insights. I think energy consumption while charging is important to only a few people, since most of us can plug in. But it's good to know anyway and rather fascinating.

Holding the second button on will change the frequency of flash mode or brightness of steady modes.
It's hard to guess how long the battery will last in between high and low. I think when it looks half as bright it's only using one quarter the power.
The flash modes are still nice and bright at the lowest speed and 100 hours is a decent amount of time. Recharge weekly on tour is fine.

There's nothing revolutionary that's changes red led technology over the last 20 years so the super flash is about as good as anything if running off disposable batteries.
Avoid the brake light function..my cat eye light is very sensitive to deceleration and it really runs the battery down.

Thanks, znomit!