Battery lights vs. rechargeable.

[si_c]

And as reasonable AA or AAA dags which can last a year or so, can be bought for about £2 for four, there's the rub - !

AA batteries can't compare to rechargeable 18650s a great AA battery has 2500mAh at 1.5V whereas a single 18650 can produce up to 4000mAh at 3.7V so their capacity is much much higher. The charging costs I quoted above was based on a dual 18650 battery with 3000mAh of capacity needing a full charge each day - that's easily 8 hours of usage for a main beam front light at well above the light output levels that a AA battery can produce. For a rear light that would be around 150hours of output on a single charge or about 1p - equivalent to 60p of charge cost assuming you ran the rear light all day every day for 365 days .

I get ages out of a pair of rechargeable AAAs in a cateye tail light. I'm not sure how long but I'm going to wave my hands and say > 20 hrs.
A set of 4 rechargeable AAs lasts a full night in my Hope Vision 1, mostly on low power occasionally high. Again a bit of hand waving and say 12 hrs. My rechargeables do tend to fizzle out when they get old. I don't use them for commuting but if I did I'd be surprised if they managed a full year of commuting use.

As to non-rechargeable AAs or AAAs lasting a year. Maybe, yeah, if you don't draw any current from them.

This is where modern rechargable batteries far outperform AAs, particularly high draw variants such as the 18650. If I'm going to be doing a long ride they're a much better choice. The Hope you refer to has a decent light output on high, but it doesn't compare to modern lamps with modern batteries.

 

[Blue Hills]

AA batteries can't compare to rechargeable 18650s a great AA battery has 2500mAh at 1.5V whereas a single 18650 can produce up to 4000mAh at 3.7V so their capacity is much much higher. The charging costs I quoted above was based on a dual 18650 battery with 3000mAh of capacity needing a full charge each day - that's easily 8 hours of usage for a main beam front light at well above the light output levels that a AA battery can produce. For a rear light that would be around 150hours of output on a single charge or about 1p - equivalent to 60p of charge cost assuming you ran the rear light all day every day for 365 days .


This is where modern rechargable batteries far outperform AAs, particularly high draw variants such as the 18650. If I'm going to be doing a long ride they're a much better choice. The Hope you refer to has a decent light output on high, but it doesn't compare to modern lamps with modern batteries.

are there any good bike lights (if front with german standard beam pattern) which take these standard 18650 cells? I have seen some which use 18650 cells but within a proprietary casing.
I avoid anything proprietary/built-in wherever possible.

 

[si_c]

are there any good bike lights (if front with german standard beam pattern) which take these standard 18650 cells? I have seen some which use 18650 cells but within a proprietary casing.
I avoid anything proprietary/built-in wherever possible.

I have a Fenix BC30 which is a great front light - it's not StVZO compliant, but it does have spectacularly good optics compared to most lights - including an optical cut off which reduces upward light throw and dazzle. Not the cheapest lamp and you need to budget more for batteries and a proper charger too. But the batteries sit in a sled and it takes about 15 seconds to remove and swap batteries. Runtime is about 12 hours for me at 200 lumens (about the same as the max brightness on your Hope), of course you can go less for longer or more for shorter.

I've had mine since 2016 and aside from a couple of surface marks it's still working perfectly.

Edit: As an aside I use LG MJ1 3500mah batteries (three sets of 2) from Fogstar with a Nitecore intellicharger.

 

[matticus]

AA batteries can't compare to rechargeable 18650s a great AA battery has 2500mAh at 1.5V whereas a single 18650 can produce up to 4000mAh at 3.7V so their capacity is much much higher.

You just did!

 

[si_c]

You just did!

Bollocks. What I meant was they don't compare well

 

[the_mikey]

My biggest gripe with rechargeable bike lights is they often contain a lithium cell with no reasonable way to replace when they become fatigued or break down, and they seem to get fatigued pretty quickly if you're using them regularly. That said, the most expensive light I ever bought (Exposure race mk5 - 600 lumen) became an expensive ornament because I wasn't happy using it for my commute because it was too conspicuous, and it works perfectly 9 years later!

 

[wafter]

I think these are the best


View attachment 626841

View attachment 626842

Fill each of those with LEDs and 18650s and you could BBQ your foes at a mile


I agree with all the sensible folk for the usual reasons and run lights with removable low self-discharge rechargeables. Less waste and cost, greater unit life and the convenience of being able to replace them with spares if they run out.

On the rear I have a nice little Moon Pulsar 2AA LED unit (actually bought two as all the later stuff has integral batteries).

I currently use a 3AAA LED Lenser head torch for the front, it's good but not ideal as it's unregulated so brightness dims with dwindling
battery.

I really want to run a regged headtorch and smaller AAA light on the bars; might consider something with Li-Ions for the former in the interest of longevity and weight.

Since all the lights run AAAs I carry three spares which covers failure of any one light.

If I did a lot of night miles on a swanky touring bike I'd consider a dynamo-based system, but as it is the lights I have are easily swapped betwen bikes, keeping things simple and cheap

 

[simongt]

If I did a lot of night miles on a swanky touring bike I'd consider a dynamo-based system,

Had a dynohub / B & M light fitted to my Galaxy last year. Great; free lighting at the flick of a switch and no dags to replace / recharge - !