Is There a "Long" 18650 Cell Out There...?

[LEDAdd1ct]

Does anyone know if there exists a "long" 18650 cell?

Still 18mm wide but with extra capacity due to increased length.

 

[ChrisGarrett]

Fastech protected Panasonic 3400 mAh NCR18650B?

They're supposed to be longer than other protected batteries in the class. I don't know if there's anything with more capacity in an 18mm round cell, like a 18700 that's made by a quality manufacturer?

Chris

 

[LEDAdd1ct]

Hi, Chris. Thanks for the reply. I'll try and clarify.

The 18700 cells you are referring to are just the dealer's way of admitting that with the shrinkwrap and protection circuit, the
cell exceeds the 65mm nominal specification.

I am speaking of cells that are 50% larger, or even twice as long, something 18mm wide but long enough to provide 5000mAh or more in the same diameter cylinder and at the same voltage their standard 65mm length cousins offer.

 

[mccririck]

I dont think there is.

 

[tobrien]

i wish there was! i've wondered this myself but i think the closest you'd get is two 18650s welded or heatshrinked together. some brand did that in the past year IIRC for some rechargeable light, maybe klarus?

 

[LEDAdd1ct]

For my project, I was thinking of running two 18650 cells in parallel, but stacked vertically instead of sideways (my tube requires them vertically).

If there is a ready made pack out there that does this, I would be happy to save the effort.

The only pack I can find already produced is too thick for my host.

So, I either have to get a larger host, or, find one already made...

@tobrien, do you know which brand and model you are thinking of?

 

[tobrien]

I honestly cannot recall. it was simply two 'regular'/easily obtained 18650s packed together in line for 8.4v topped off. it was a 3100mAh cell pack iirc

 

[VegasF6]

Something like these?
http://www.batteryspace.com/customi...728wh2x18650endtoendpackedwithpcb4wireic.aspx

 

[AnAppleSnail]

I've thought of ways to cook this up with shrinkwrap and thin metal ribbon, but it's just UGLY having a (+) and (-) so close to each other. The diameter restrictions make the 'corner' around the cells tricky, too.

 

[LEDAdd1ct]

I honestly cannot recall. it was simply two 'regular'/easily obtained 18650s packed together in line for 8.4v topped off. it was a 3100mAh cell pack iirc

That is in series. The reason I specifically asked about a "long" 18650 is because I need the same voltage, not twice as much.

Something like these?
http://www.batteryspace.com/customi...728wh2x18650endtoendpackedwithpcb4wireic.aspx

I already considered and dismissed that unit; thank you, though. The maximum outer diameter, with PCB, is 21mm, making it too large for my intended host.

I've thought of ways to cook this up with shrinkwrap and thin metal ribbon, but it's just UGLY having a (+) and (-) so close to each other. The diameter restrictions make the 'corner' around the cells tricky, too.

Very tricky, yes, but not impossible. I am not quite sure how to pull the positive of the bottom cell to the top and the negative of the top cell to the bottom.

 

[RedForest UK]

The 65 part of 18650 refers to the cell's 65mm length, so if you want a longer version you would have to search for 18800/18900 etc. Unfortunately a quick look on google doesn't bring anything up..

 

[LEDAdd1ct]

Thanks for the reply. Yes, I know the 65mm refers to the length...in the OP, I noted that

"Does anyone know if there exists a 'long' 18650 cell?

Still 18mm wide but with extra capacity due to increased length."

The quotes are to indicate acknowledgement that it would not technically be a 65mm cell, but, that in common parlance, it might closely resemble one, in the same way that a 26650 is sometimes referred to as a "long C cell."

Unfortunately, simply adding mm to the "65" component did not help me on Google, either.

 

[tobrien]

ah sorry about that. I didn't interpret your statement correctly :/

it'd be so awesome if that existed... or at least if we could find it as 2x 18650 length at the same 3.7 nominal volts. I'd be able to stuff it in my bored C3 without having to use 'special' P60 drivers

 

[bshanahan14rulz]

Yeah, I'm thinking you may have to go with the two paralleled 18650s in-line. Make sure to use some good polyimide and shrinkwraps, maybe even a hard plastic separator in places where you can.

I'm guessing there is not a driver for 2 cells for your application?

 

[LEDAdd1ct]

The plan is to drive a Gene Malkoff Stinger LED dropin in a fivemega 2x18650 host off two LG D1 3000mAh 18650 cells in parallel from 4.35v to 3.0v for double the runtime. There isn't a ton of room in there, however.

Moving to the next tube diameter for "C" alkaline batteries will give plenty of room, but the additional thickness, substantially larger than 18mm form factor, is not desired.

 

[franzdom]

I have a light that won't work with IMR red 18650 but does work with the longer protected black AW battery...

 

[CMAG]

if you removed the protection and used the flat wire the protection uses to bring + to top of battery with both + terminals touching you only need to bring + from middle to one end

 

[RedForest UK]

Thanks for the reply. Yes, I know the 65mm refers to the length...

Unfortunately, simply adding mm to the "65" component did not help me on Google, either.

Ok, no worries. I hope you can work out a way around it. I'm sure I even saw a 141000 cell somewhere (probably under a different name) with the length of 2x AAs but a voltage of 3.7v. I think a similar cell is used as a proprietary battery by someone (maybe a Nitecore 2x AA light).

There was also an old thread where someone stated that certain manufacturers would make whatever size you wanted if you could make a large order of cells (200+ though or even more I think).

 

[VegasF6]

I think it's going to be quite a challenge to find what you are looking for. Wouldn't it be more prudent to simply consider a switching power supply and use 2 series batteries?