Li-ion Battery Safety and Shopping Guide

I'm aware, I put it in there twice because I wanted it under IMR (since it does such high currents) and under LiFePo4. I understand this is not technically correct since it is not LiMn cell, so maybe I should remove it from the IMR section?

Technically speaking, the CGR18650CH isnt LiMn either..^^

But I would keep LiFePo4 cells out of the LiIon lineup, those are too special and only very few people actually use them.

Btw.: what about 32650, 26650, 26500, 22650, 18500, 17650, 16650, 14650, 10440, 10180? (yes, I'm here to molest you)

Oh, and where did you get the graph of the Sanyo UR18650W? I ordered W2 and WX recently, waiting for them to be tested..

Yup, it doesn’t belongs in IMR section.

True, but I feel it should be there. I guess I'm sorting by function not strictly chemistry. I'll leave the LiFePo4 batteries in for the smaller batteries at least because some lights can take a 3.3v battery but not a 4.2 volt battery. 16650, 18500, and 10440 will be added later today when I get a chance. 32650, 26650, and 32600 will be added at some point in my 3rd comment which is for bigger cells.

The graph actually came from the datasheet (which I did link to already ), which is here.

Ok, if both of you think that it is getting removed now. :)

Thanks — nice work… very useful.

On the subject of XXXfires, maybe it’s worth mentioning the lifecycle of a fake:

- laptop/recycling pull (or worse, as we’ve seen little lipos wrapped in 18mm tubes)

- new shrink wrap from taobao (EDIT: worse than I thought "Make" your own UltraFire 18650s! — even shows Panasonic wrappers at http://item.taobao.com/item.htm?spm=a1z10.3.0.77.saBKb5&id=10193523421& )

- off to ebay (or a semi-reputable vendor that’s being cheated)

  • and into some unsuspecting flashlight

Scaru, if you continue to excel in this manner, you will have to "drop the diaper", and start wearing long pants.

Keep up the good work!!Wink

begging for a spreadsheet…. i know some do not have excel but open office is free and i think it would solve a lot of organizational problems. my apology if there is a spreadsheet in here somewhere i just could not wade thru it all

ken

I have excel, what would you like in the spreadsheet?

Ok, done with the smaller batteries. Tomorrow I will tackle the larger batteries.

Done with 26650, after all 2 in the morning is tomorrow. :P

32650 and 26500 will be added tomorrow. If anyone has any further suggestions post here or PM me. Also, if someone can clarify what is wanted in a spreadsheet that would be appreciated.

Why is Keeppower 16650 “Unspecified internal cell”? It uses the same UR16650ZT as Intl-Outdoor 16650. :stuck_out_tongue:

Choosing batteries: Scaru, could you please point out to beginner purchasers that that there are three main types of contact points on the positive end. Flat, button and nipple. The “button” term can be misleading, because its generally used to describe both button and nipple. Some flashlights with reverse polarity protection such as Eagletac, require nipple tops. A nipple top has a smaller diameter button than a true button top and is usually raised up a little more.
It is good to double check when purchasing, because photos of button tops sometimes make them appear to be smaller in diameter and result in awaiting a new battery only to find it will not work without the aid of a magnet.

…safety and use of magnets?

I will add info on that today, :slight_smile:

Oops, I knew that. :P As always, thanks for keeping me honest. ;)

Ok, done with the larger cell section unless anyone has any requests. I added this info about button tops and magnets.

"There are 3 main types of positive contacts used on the batteries. First, and most common is flat top; these are a simple metal contact no higher than the surrounding label. This is the way batteries generally come from the manufacturer. (Does not apply to NCR18650 series) Then there is raised top, or button top, this has the same contact size as the previous one, but the whole surface is raised. This is needed in lights where the batteries are stacked to ensure contact. Then there is nipple top, this has a small raised top; much smaller. Some lights that have mechanical reverse-polarity protection require nipple tops.

People often use small round magnets to create a a nipple top from a flat top. To do this one simply places a magnet on the top of the battery, this does come with a risk. The magnet can easily slide out of space and short out the battery, it is for this reason people often place a dab of superglue under the magnet. An example of one of these magnets is this. "

And I'll ask one last time, what would you guys like in a spreadsheet?

Ok, one last bump before I remove the "In Progress" label. Shadowww come over here and tell me what I screwed up. ;)

I’m afraid you’ll need HKJ for that :stuck_out_tongue:

Yay, I got the shadowww seal of approval. ;)

Ok, this one is done! And at 44 pages it is my longest article yet. :)