Protected 18650 Cells No longer than 65 mm?

13 posts / 0 new
Last post
meeshu
Offline
Last seen: 1 week 6 days ago
Joined: 06/19/2012 - 06:58
Posts: 79
Location: NZ
Protected 18650 Cells No longer than 65 mm?

It appears that protected 18650 cells are longer than non-protected 18650 cells due to the addition of protection circuitry. But couldn't protected 18650 cell length be adjusted so that the total length is still 65 mm as per non-protected 18650 cells? Of course there would probably be a slight reduction in protected 18650 cell capacity (in mAh) due to some cell space being taken over by the protection circuitry.

But, are there any known protected 18650 cells presently available with a length of 65 mm?

Flashlights: Klarus Mi1c, 3 x Manker E11 (two CW and one NW), 2 x iTP SA1, JetBeam JET μ (unused), JetBeam JET I MK (sold), Klarus Mi10 (unused) 

Chargers: Miboxer C2-6000, Miboxer C4-12, iSDT C4, OPUS BT-C3100, OPUS BT-C2000, LaCrosse BC-900, Voltcraft IPC-1, Tenergy TN268, plus a few smaller chargers

tundraotto
Offline
Last seen: 51 min 17 sec ago
Joined: 10/12/2018 - 13:38
Posts: 49
Location: United States

No – I don’t think so

Lexel
Lexel's picture
Offline
Last seen: 49 min 28 sec ago
Joined: 11/01/2016 - 08:00
Posts: 4568
Location: Germany

the cells are standardized by form factor
PCB is sort of aftermarket device on it

Jerommel
Jerommel's picture
Offline
Last seen: 1 week 21 hours ago
Joined: 01/04/2014 - 13:18
Posts: 5724
Location: the Hague, Netherlands

There’s also an extra button top on protected cells.
That adds another 1mm or more.

You could buy the protection boards yourself and add them to unprotected cells, and not use a button top.

2Q19

meeshu
Offline
Last seen: 1 week 6 days ago
Joined: 06/19/2012 - 06:58
Posts: 79
Location: NZ

Comments noted, thanks!

I didn't think there were 65 mm 18650 protected cells around as I haven't come across any (so far).

In theory it should be possible to make them, but it may not be (economically) feasible as there would be a slight capacity loss compared to an equivalent sized non-protected 18650 cell? 

Flashlights: Klarus Mi1c, 3 x Manker E11 (two CW and one NW), 2 x iTP SA1, JetBeam JET μ (unused), JetBeam JET I MK (sold), Klarus Mi10 (unused) 

Chargers: Miboxer C2-6000, Miboxer C4-12, iSDT C4, OPUS BT-C3100, OPUS BT-C2000, LaCrosse BC-900, Voltcraft IPC-1, Tenergy TN268, plus a few smaller chargers

Jerommel
Jerommel's picture
Offline
Last seen: 1 week 21 hours ago
Joined: 01/04/2014 - 13:18
Posts: 5724
Location: the Hague, Netherlands

They just don’t make 62 or 63mm tall cells.
Next step down is 50mm, but there’s a very limited amount of choice in that size.
There are a few rare sizes on the market though, like 16500, but you can’t expect them to be of the same quality as the well known and loved mass produced Japanese branded cells.
Chinese brands are starting to produce similar quality, but they make what the market demands, which is mainly 18650 size.

Technically speaking, of course, it is possible to make a shorter cell with a little less capacity.
But like you i haven’t seen 18600 or 18630 cells.

Why are you looking for shorter protected 18650 batteries?

2Q19

Enderman
Enderman's picture
Offline
Last seen: 46 min 41 sec ago
Joined: 11/03/2016 - 22:42
Posts: 3782
Location: Vancouver, Canada

No, because then it would no longer be an 18650 cell.
The manufacturers making the cells (samsung, lg, panasonic, etc.) make the cells to spec, exactly 65mm long.
A protected 18650 would have to be longer, it impossible to make a 0 thickness circuit.
If you wanted something shorter it would no longer be 18650, it would be 18500 or something like that.

Lexel
Lexel's picture
Offline
Last seen: 49 min 28 sec ago
Joined: 11/01/2016 - 08:00
Posts: 4568
Location: Germany

If you got torch with LVP and a quality charger there is no real need for PCB
It can trip if you put in one battery wrong directed in a light with multiple parallel cells but no more real value given

If things go wrong on high drain betteries usually springs act as fuse, if not the cell disconnects the short when venting

meeshu
Offline
Last seen: 1 week 6 days ago
Joined: 06/19/2012 - 06:58
Posts: 79
Location: NZ

Some lights and some chargers will not take 18650 cells longer than 65 mm. And in some lights without any (over discharge) protection, it might be more appropriate to use protected 18650 cells. These are the reasons why I'm querying the existence of any protected 18650 cells with a length no greater than about 65 mm.

Flashlights: Klarus Mi1c, 3 x Manker E11 (two CW and one NW), 2 x iTP SA1, JetBeam JET μ (unused), JetBeam JET I MK (sold), Klarus Mi10 (unused) 

Chargers: Miboxer C2-6000, Miboxer C4-12, iSDT C4, OPUS BT-C3100, OPUS BT-C2000, LaCrosse BC-900, Voltcraft IPC-1, Tenergy TN268, plus a few smaller chargers

Phlogiston
Offline
Last seen: 18 hours 48 min ago
Joined: 10/27/2016 - 16:57
Posts: 683
Location: Scotland

I wonder if anyone’s ever wrapped an 18500 with a protection circuit and a spacer to make it up to exactly 65mm?

EDCba
Offline
Last seen: 6 hours 33 min ago
Joined: 08/25/2018 - 01:10
Posts: 106

The common argument is that there’s not enough demand to make a shorter 18650 cell, that with protection circuit makes it exactly 65 mm. But I find it odd that they can do this for 14500 and 16340 – all the major brands have USB rechargeable batteries, with a micro USB port, that are no longer than unprotected cells. Surely there’s even less demand for 14500 and 16340.

Lightbringer
Lightbringer's picture
Online
Last seen: 6 min 28 sec ago
Joined: 08/30/2016 - 14:12
Posts: 6750
Location: nyc
EDCba wrote:
The common argument is that there’s not enough demand to make a shorter 18650 cell, that with protection circuit makes it exactly 65 mm. But I find it odd that they can do this for 14500 and 16340 – all the major brands have USB rechargeable batteries, with a micro USB port, that are no longer than unprotected cells. Surely there’s even less demand for 14500 and 16340.

Dunno about 16340s, but as for 14500s, there are 14430 cells, 43mm long vs 50mm, so that’s 7mm to stick in a button-top, protection circuit, etc.

Maybe protected “14500s” are just that, 14430s in drag.

Anyone ever skin one to see what’s in there?

09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0

Enderman
Enderman's picture
Offline
Last seen: 46 min 41 sec ago
Joined: 11/03/2016 - 22:42
Posts: 3782
Location: Vancouver, Canada

EDCba wrote:
The common argument is that there’s not enough demand to make a shorter 18650 cell, that with protection circuit makes it exactly 65 mm. But I find it odd that they can do this for 14500 and 16340 – all the major brands have USB rechargeable batteries, with a micro USB port, that are no longer than unprotected cells. Surely there’s even less demand for 14500 and 16340.

None of the major brands have USB rechargeable batteries.
Samsung, LG, panasonic, etc. None of them do.

The reason you can find 16340 or 14500 cells with built in charging is because they are using a smaller size cell inside, they aren’t real 16340 cells or 14500 cells.
The top brands don’t make 16340 or 14500 cells so the manufacturers making these ‘built in recharging’ cells are forced to use some lower performance cells from smaller manufacturers in china.
That’s why 16340 and 14500 cells have far less Wh/kg and Wh/L than the 18650s made by the major brands.