cycle lamps and batterys

[[XAP]Bob]

well have a look at the Torchy website - thanks for that very interesting

some of the lights - 1000 lumens? really? the Lidl ones are 40 or so and I thought they were good

Dodgy measurement, and a photon scatterer probably.

Great if you are racing downhill at the dead of night, and not being chased...

[freiston]

I ended up replacing my Fenix BT20 light (running on 2x 18650 batteries) with a dynamo set-up (front lamp B+M Lumotec IQ Cyo Premium T senso plus [wish they gave it a shorter name]) in 2015. Apart from the B+M being a better light IMO, I much prefer the convenience and ever-readiness of the dynamo.

I did buy a nice Fenix hand torch (PD35 Tactical) so the 18650 batteries didn't go to waste

[mercalia]

Where have you been?
18650 cells are fairly common in LED bike lights, but mostly either built in, or with 4 in a separate battery pack. Bike lights you could swap cells in are relatively uncommon, but there are some - eg the Fenix BC30. Torches are more common.

4300 mAh will come under the heading of "lies, damn lies, and marketing". Half of that is more likely.
18650 cells are a fire hazard, due to shorting, physical damage, or injudicious charging. You are, for example, not permitted to take them on an aeroplane.
They are relatively expensive (~£15?), with cheap ones likely to have been recycled from laptop battery packs, with possibly very low capacities.
They also have a time-limited life, and will start to lose capacity after a few years.

well seems you are right

didnt know this part of commerce just a den of thieves.

Just lies lies lies lies and more lies -

A youtube testing of a 9900mah piece of rubbish

[youtube]dca8NVGTOlk[/youtube]

such blatant lies should not be allowed. Quite stunned

[resus1uk]

My Hope front lamp is adequate but rapidly flattens NiMh batteries and seems voltage sensitive.
The NiMh batteries are 1.2 volts each. This winter I used NiZn batteries from Maplins with the appropriate charger. No problems with rapidly failing power when on load.
A A size so fits the spare battery pack

[andrew_s]

well seems you are right
didnt know this part of commerce just a den of thieves.
Just lies lies lies lies and more lies -
such blatant lies should not be allowed. Quite stunned

It's a case of "if it sounds too good to be true, it's dodgy"
An 18650 li-ion cell should cost something in the £10-£20 range, and have a capacity between about 2000 mAh and 3300mAh.

The cells themselves are widely used - a laptop will use about 8 of them, and a Tesla car* will use something like 9,000 of them. When a laptop dies and goes for recycling, in the dodgier parts of the world the battery pack is broken down into individual 18650 cells, new wrappers are put on, and they are sold with whatever marketing blurb suckers in the most gullible people. If the battery pack is just old, cell capacities will be something like 1000 mAh, but quite often the pack is duff because one of the 8 or so cells has failed, in which case there will be 1 or 2 cells that have a capacity of maybe 200 mAh, and 6 or 7 with capacities of 2000 mAh or so. What you actually get will be luck of the draw.

* a top of the range model S has enough 18650s to give a 100 kWh battery pack, giving a range of up to 400 miles, and a 0-60 time of 2.5 sec (but not both together).