Cell phone batteries as custom light source?

[gsk3]

Has anyone ever tried to use an old cell phone and its battery as a power source for a light (bike light, etc.)? Seems to me they're good batteries, cheap as dirt, small, and have a cheap smart charger....
Ari

 

[abvidledUK]

Nokia 1101.

Has built in torch !!

Dim, but bright idea.

 

[gsk3]

Heh. I was thinking more along the lines of basically free 3-4V Li-Ion driving a 5W LED.

I've got more AA NiMHs than I know what to do with and a good charger, so I'm not going to persue this. Was curious if anyone has though.

Ari

Nokia 1101.

Has built in torch !!

Dim, but bright idea.

 

[Y-Wrench]

Those battery's have low mAh so runtime would be an issue, unless you strung several together.

 

[gsk3]

Ah, pity.
Ari

Those battery's have low mAh so runtime would be an issue, unless you strung several together.

 

[eebowler]

gsk, that same idea went through my head a few months ago when I could have gotten a cell for <$10US but the lines were long and the phones low in stock. Ah well.

 

[bombelman]

Most of them are aroung 300~400 mA p/charge.
You would think cheap, but for <$10, you could get AW R123 3.6v @750mA.

I think also the form-factor limits use for cylindrical enclosures...

 

[greenLED]

The Indium puck uses a square li-ion cell phone battery.

 

[gsk3]

I think also the form-factor limits use for cylindrical enclosures...

Ah, but for flat enclosures (e.g. bikes)....

Ari

 

[Martin]

I put together the electronics for a light that uses these batteries.
A friend of mine has been very happy with it for abt 2 years, now.

And well, they are no old cell phone batteries, they are new ones from China, dirt cheap on E..y

 

[eebowler]

bombelman, maybe so, but at least for <$10 I get battery AND smart charger!

 

[bombelman]

bombelman, maybe so, but at least for <$10 I get battery AND smart charger!

Where ? In T&T ?
(BTW, check some nice pics of Destra and Allison Hynds on my site www.bombelman.com :naughty: )

Martin, nice design, great build ! How much juice do your cells pack and how is drop-out rate ?

Cheers ! :rock:

 

[Martin]

..How much juice do your cells pack and how is drop-out rate ?

Still on the first cells. The Luxeon I is being driven at 400-500mA and the batteries are labeled 3x 1700mAh = 5100 mAh (which is probably exaggerated, Chinese style). The light is beying used for hikes or MTB trails up to 2 hours continuously before it's recharged. Never ever the batteries were depleted.

 

[macforsale]

*

 

[Martin]

Mike, the fellow who made this (it's not me, I merely contribute the electronics) is actually spending a lot of time with SolidWorks. Well, he can't use the company resources for his personal hobby and he cannot afford a SolidWorks license at home.
In my workplace we have design packages that cost so much, that we work 2 shifts. And licenses won't be cheaper in the future.
Expect to see more art.