Choosing the right 18650 Lithium-ion cell

18650 cell battery technology

Laptop batteries have been using 18650 type Lithium-ion cells for many years. With phones becoming more powerful, their batteries often fall short of the energy a user demands from a phone. This lead to a hot market for power banks. A lot of power banks have one or many 18650 type cell in them too.

An 18650 based Lithium-ion power bank

The real boom in demand for 18650 Lithium-ion cells has come from the Electric Automobile market, with Tesla pioneering the use of these cells in the Model S and X battery.

It is true, that in the future we may shift to another size for the cylindrical form factor which offers higher energy density, but at this point in time the 18650 form factor supersedes market demand.

We've written this article to help you find the right 18650 cell for use in our products such as the ION board and SC4 board.

18650 cells can be found from a lot of major manufacturers including Samsung, LG Chem and Panasonic. The demand for these branded cells is high due to the booming EV market, which makes them a little hard to find for retail buyers looking for just a few cells.

The picture shows a Samsung 18650 cell, but the brand is PrettyW most likely a Chinese secondary market cell. You should not be paying $5 a piece for such cells.

The best place to start your search is Amazon and Ebay. The search term should be "Flat top 18650 Lithium-ion cell". While it is possible to find these cells for around $1 a piece, their prices on Amazon and Ebay are usually around $4 a piece. However, when you're buying 1-2 cells, it's fine to pay the extra bit as you don't need to worry about shipping, customs, etc.

Another example of an Amazon listing using pictures of an LG Chem 18650 cell, but the brand here is M&A. Do not pay $6 a piece of such cells!

Does this mean, you can't trust the secondary market cells? That's not the point here. You should definitely be careful when purchasing secondary market cells, and most importantly you should not be paying premium price for them.

At the time of posting this, I was not able to find suitable cells for purchase from Amazon, probably due to limited availability right now because of Covid-19. But, I did find a suitable listing on Ebay.

What I'm looking for in the listing -

1. Picture should be depicting the right brand for the cell
2. Cell brand should be specified in the product listing
3. Shipping from a location that is local to me to avoid shipping delays and customs issues
4. Priced appropriately. This should ideally be around $8 for 2 cells, but at this time, this seems to be the best offer I could find due to limited availability of cells.
5. Should be Flat top, not button top to make sure that they fit our products

If you're looking to order cells in larger quantities, you can take a look at some of the distributors such as
1. Battery Bro
2. Liion Wholesale

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