[Solved] Source for "button" or "flat" top 18650 Li-Ion

All my 18650's that I use for these electronic projects, I got from cracking open laptop batteries.  

Posted by: @darup

Looking for a source for high-capacity 18650 Li-Ion.  Flattop or Buttontop are okay. amazon has a very limited selection and the choices are, from what I have found, rather low-capacity.

Presently, I have to share the cells from my flashlight with my project that also requires 18650 cells.

(I hope this is okay to post here?)

@darup I get mine (10 on the way nbow) from Aliexpress. Be CAREFUL however, anybody claiming mnore than about 3400mAh is a fraud, I saw some 9,900 and 19,900. Remember,  batteries are chemistry, you can literally ballpark a batteries capacity by weight and/or physical packaging.

Button tops are safer than none, and ALWAYS insert button top first, there is a very real chance of direct short from the +button to the -case. I was not paying attention 2 days ago and had a nasty surprise myself. BTW, my latest price is 10 batteries for $20.52 CDN and about $10 shipping.

DAM, I just noticed they are labelled 5000mAh so are probably fake, used as well I bet. These will most likely have to go to hazardous waste. The 18 in 18650 is the diameter in mm and the 65 is the length in mm. That size package yields a battery of about 3,400mAh, it can't be any more if the form factor is the same and the chemistry the same. I will be checking these so called 5,000's very carefully, I have s load tester now so it will be easy.

EDIT - They could be more if the chemistry is something more dense than LiPO but I doubt they are. Fortunately Aliexpress has a good dispute resolution facility.

Posted by: @zander

The 18 in 18650 is the diameter in mm and the 65 is the length in mm. That size package yields a battery of about 3,400mAh, it can't be any more if the form factor is the same and the chemistry the same.

Real good advice @zander.  Thanks.

@will - I have to keep up our reputation...

Posted by: @zander

CAREFUL however, anybody claiming mnore than about 3400mAh is a fraud, I saw some 9,900 and 19,900.

Why I tear apart old laptop batteries.  With all the lawsuits over "exploding" laptops, they (Dell, HP, etc) went with the best cells in the world... typically Panasonic or equivalent.  I'd rather use used Japanese batteries to Chinese "magic" batteries any day.

Usually it only takes one or two cells going bad (due to poor laptop charging habits) for someone to throw out a laptop battery brick.  I charge and bench test capacity each cell.  Often, all the rest of the cells will exceed rated capacity.  

@inq Actually it's the same cell manufacturers in the case of the Chinese Panasonic cells. The reason for the old exploding scare is chemistry. I sleep on 6 x 100AH LiFePO4 batteries and don't worry. Lithium-Ion cells are more prone to thermal runaway. The old Tesla batteries were also prone to thermal runaway but they have switched/switching to the much safer LiFePO4. As always more untrue information on the net than not.

Posted by: @zander

The old Tesla batteries were also prone to thermal runaway but they have switched/switching to the much safer LiFePO4.

So far, only the China factory uses the LiFePO4 and only for the standard range models.  The high-performance and long-range model still use the LiIon versions.  Their new battery (4680) is also still a LiIon.

@inq So in this case it's the Chinese with the better battery. I remember when people wouldn't but Japanese transistor radios. 

Posted by: @zander

@inq So in this case it's the Chinese with the better battery. I remember when people wouldn't but Japanese transistor radios. 

It depends on your definition of better. 

LiFePO4 is far safer in the hands of the general public.  It is near impossible to get it to run-away overheat, fire, explode etc.  The standard even includes a test to drive a nail through all the plates and the resulting short-circuit NOT cause catastrophic (dangerous) failure.

However, the energy density is significantly better for the LiIon used in all other Tesla's... Thus lighter, faster, or more range.  That is why LiFePO4 is not in the long-range or performance models.

However, the deciding factor that Tesla made was not based on safety, it was based on the lack of Cobalt in the LiFePO4 batteries...  Thus cheaper and with less long-term supply headaches.  Plus, they source the LiFePO4 from CATL so it does not take away from their own vertical production of LiIon batteries, so it adds to their production versus taking away some of their own production ability.

@inq I like safe.

@zander - I like sports cars.  I test drove a model S in Ludicrous mode.  It makes my sports car feel like lead sled, but not enough to replace it.  Although, I did sign-up for a 3-motor Cybertruck.  Doubt I'll buy it though.

Posted by: @zander

Aliexpress

So, this thread expanded to two (2) choices:  1) "an Oops maybe fraud;" and, 2) "crack open old laptop battery-bricks!

Is Aliexpress still a good choice since it seems the current order, mentioned, may be a problem?

Then what is the "SAFE" way to crackOpen a lapTop battery, separating the badCells from the goodCells that no longer charges?

Please do not leave me hanging!  I can do that all by myself ... (grin).

BTW, I liked the clarification of the cell nomenclature (Width and Length) to the product number!

Posted by: @inq

drive a nail through all the plate

I naturally do stupidStuff - it has gotten me where I am today; so, I solumnly SWEAR not to pound a nail through all the plates -- I guarantee I will not do that (hmmm, maybe it would/could be interesting? -- movingOn)

Posted by: @darup

Looking for a source for high-capacity 18650 Li-Ion

So now, what is a reliable source for an equivalent 18650 xx; where xx is a type that will be usable, safe, and, most importantly fit-and-work!

.

Posted by: @zander

LiFePO4 batteries

If I understand all of this, my quest is for a supplier of LiFePO4 cells rather than Li-Ion?  Okay, so now I am almost clueless and if not that, I am maybe confused about what I want to purchase in the 18650 format?

Thank everyone for the input.  May I ask a favor ... I certainly found all of this enlightening; though not being within the scope of my expertise, "Would a dumb'd down summary be possible?"

@darup aliexpress is hundreds of stores, one bad one does not affect the others. Just do a search, the cheapest will come up first, make sure it's panasonic or one of the others but only 3400mah, then check shipping cost, sometimes the 2nd or 3rd per uit cheapest is the lowest cost due to shipping. Batteries are expensive to ship.

And yes lot's of guys crack open laptop batteries. Just remenmber they are ALL used, some are finished some will have a little life, it's a crap shoot and aliexpress may still be cheaper.

@darup If you want a non chinese source just google 18650. You are likely in USA, I am in Canada so no point me doing it.

Did the suggessted search learning more along the way.

Now, I see why you mentioned buttonTop as the "choice" for 18650.  Up until now "Flat" or "Button" made no difference.  The "Button" types were annoying because the nipple/button continually got in the way; they were the lesser cost so that is what I got.  For the most part that is all that I have ever purchased.

From now on, it will be "Protected Button Top 18650."

Thanks for protecting me from myself -- again!

Have not found the pricing I like.  I'll keep looking.

@darup - Several things.

I know many people have different opinions on who is acceptable.

• I have had no good experiences dealing with Ali Express.  Maybe it's changed.  They don't expect to have to replace or replace... It costs more to ship back than the parts cost.
• eBay, I've done hundreds of orders many to China.  Again long time coming, but the three or four bad products, the seller fixed to my satisfaction.  The one that didn't, eBay backed me up and refunded me.  I was out two months wasted time.
• Amazon, get it in one/two days, return it if it isn't what was delivered.

To my knowledge all 18650 are LiIon.  All the LiFePO4 cells I am aware of are either pouch or bricks.  I don't recall any that were cylindrical.  

I might have missed your post, but I didn't read what your using them for.  I would make different decisions depending on their purpose.

As far as tearing up laptop batteries.  I only use these for my hobby or in flashlights.  I doubt I go building a Power Wall with them, but many people do successfully.  Cracking the plastic boxes and pulling out the 18650 cells is a pain and surprising difficult.  They don't want people doing it.  Good versus Bad cells is easy.  Typically the laptop say the brick is bad.  When you open it up most cells will be good.  Typically 1 or 2 will be bad.  Bad is when V < 2V.  Dispose of them.  All the rest will likely be 3V and above before charging.  Get true 18650 LiIon chargers.  They're not expensive.  New or used, you still have to get chargers.

If you're curious, I got a charger/discharger/tester.  It can do a full discharge test on them and tell you exactly how much capacity is left.  I have this one, but I'm sure others are just as good.

https://www.amazon.com/Havcybin-Battery-Balance-Discharger-Batteries/dp/B093P2L2XC/

Just now, in another thread, I calculated the remaining capacity of a cell that is at least twenty years old, has been in a box for at least three years and still had almost 4.1V reading (4.2 is maximum full)  3.7V is nominal and fully discharged is 2.5V.  Without topping it off, it showed 85% of original capacity.  It was free.  Maybe, I need to do an official test on it to see if that was a good estimate.

VBR,

Inq

PS - Just don't nail a LiIon... that dog will bite uuuuuuuuu!