DIY Power bank for 18650 PROTECTED battery with sufficient space for it

Please help in in desperate search for a power bank from eBay that would have SUFFICIENT space inside it for a protected 18650 Panasonic.

Unlike the rated battery, this one's length reaches up to 69-70 mm.

I have already purchased many different kinds of DIY power banks from eBay (China). However, ALL OF THEM !!! were for unprotected cells only. (Max. lenght of battery about 65 mm).

I have loads of protected 18650s, so I would love to use them. I only have 2 unprotected, which is few for all-day-long summer bike rides' electronics. Help me make use of several pieces' 3000+ mAh for each cell...

Is anything like that even out there? As stated, all of the product I desperately bought in hope to be large enough were only for cheap Chinese unprotected cells.

Thanks a lot.

You didn't specify whether you need a multi-cell powerbank or not, but the Thrunite C2 can house a long protected 18650.

Up to 68,5mm:

http://powercartel.com/teardowns/tomo-v8-4-soshine-e3-diy-usb-power-bank-teardown/

Thank you for fast replies.

Glad these are out there as well.

However, how do I know if the space inside is big enough for a protected 18650?

For example, this one looks very similar to Tomo V8-2:

http://www.ebay.com/itm/Portable-2x...hash=item3f74bf82e3:m:mMPC9hT3Rkf1AMGSXbtxG5g

Does there have to be a brand name with it, for it to have these dimensions for protected 18650 batteries?

Thanks.

I don't think you are going to find a power bank DIY kit for protected cells unless perhaps you can weld the cells in one yourself perhaps because all the ones with springs in them the cells fit in there tightly and this is pretty much required because of the current draw from them if tight enough with protected cells would be perhaps too lose with unprotected cells and either bounce around and not make good contact. What you may have to do is buy some shrinkwrap and tear the protection circuitry out of a few of them and rewrap them for use in kits. If you had a pack welder you could either buy a power bank and strip the circuitry from it or a power bank circuit and make your own.

There is one thing that will work that I have but it isn't a sealed power bank kit. I have an Opus BT-C100 charger that also works as a single cell power bank and it will accept protected 18650 batteries. You could with this charger have a case of batteries and swap them in/out of the charger. It will charge at 2.1A if that helps.

As someone mentioned the Thrunite C2 has plenty of room (don't buy the N1. It cannot provide more than 1A but with the datapins shorted phones will try to pull more and it cycles rapidly).

This unit has very long bays that should work with any protected cell (even some I had that were almost 74mm and wouldn't fit my i4 and D4 chargers before I ripped the buttons off--but left the protection boards):
https://www.amazon.com/gp/product/B01JUBO10E/?tag=cpf0b6-20

It has independent circuits for all 4 bays. The downside of it is that is is rather bulky compared to the others.

This unit is very compact (only fits unprotected) but has the cells hard paralleled in the battery compartment (whether it is on or off). You are essentially building a P4 pack with all the standard precautions that apply to pack building:
https://www.amazon.com/gp/product/B01L77JXRA/?tag=cpf0b6-20

Mike

I have a Tomo V8-4 which runs on 4, or 1, 18650s and I tried a protected Redilast 17670, which is a 16650 Sanyo 2100mAh cell and it measures about 68mm, but I have some more room, so I'm guessing that 69mm, or even 70mm would work.

Chris

I think the white Soshine YM-E3-4 and the black Tomo V8-4 are identical inside. I have 69.6mm Button-top protected cells and they barely fit.

Mike

Arizona_Mike said:

As someone mentioned the Thrunite C2 has plenty of room (don't buy the N1. It cannot provide more than 1A but with the datapins shorted phones will try to pull more and it cycles rapidly).

This unit has very long bays that should work with any protected cell (even some I had that were almost 74mm and wouldn't fit my i4 and D4 chargers before I ripped the buttons off--but left the protection boards):
https://www.amazon.com/gp/product/B01JUBO10E/?tag=cpf0b6-20

It has independent circuits for all 4 bays. The downside of it is that is is rather bulky compared to the others.

This unit is very compact (only fits unprotected) but has the cells hard paralleled in the battery compartment (whether it is on or off). You are essentially building a P4 pack with all the standard precautions that apply to pack building:
https://www.amazon.com/gp/product/B01L77JXRA/?tag=cpf0b6-20

Mike

Click to expand...

The first link would be really perfect for 4 cells.

However, I'm looking for 1-2 cells at most. I want it to be small, compact. Would you suggest any similar to it?

I tried similar brand and searched "e4c soshine". Although it comes from the same brand, people on Amazon write they're disappointed with this particular one.

So any other for 2 cells at most?