But they are expensive, even direct from China, and a good many are intercepted because customs will arbitrarily decide these types of batteries are too dangerous to ship. They can be had on Amazon, but it's very hard to tell the fakes. Some of these fakes can fool some of the experts.
I decided to take my chances on Amazon, and I have heard of DoingOutdoor, so I bought two of their 6 pack of these cells for about $37 each pack. Pricey, but much cheaper than anywhere legitimate that I've found. I figured that if they weren't legit, then Amazon would take care of me.
Here is the official spec sheet from Panasonic, in PDF format.
The cells are wrapped individually in little cardboard boxes, so they are safe to ship. I doubt Amazon would allow anything unsafe since their name is on it too. They sure look legit to me. The color of the cells, weight, etc., all feel good in my hand.
I figured the best way for someone like me to prove these cells are legitimate is to measure and weigh them, and test the capacity, both anecdotally in my 4x18650 Ruinovo USB power bank, as well as my analyzing charger. There's no way a fake is going to measure anywhere near 3400 on the charger, though it takes a LONG time to test these cells, because the charger does a full charge, discharge and then charge again, at 500 mA!
Weights & Measures
Weight and length both look within spec. I took a random cell out of the box, and got 46 grams on my calibrated scale, and 65.01 mm on my calipers, which wanted to be at 65.00 but kept bouncing back and forth.
|Panasonic NCR18650B Unprotected Cell - Caliper Measurement|
Test #1 - USB Power Bank
This power bank had 4 decent and matched Sony cells harvested from a laptop battery. They all tested near 2,000 mAh before I put them in, so this has made a decent power pack the last year or so. And other than scratching and killing a couple electronic gadgets from being heavy and aluminum, this Ruinovo power bank has really done well, surviving being carted all over the country in the truck.
The unit charges from a micro USB port at 1 amp. When I first plugged it in, it registered about 25 percent charge, and spent 11 hours charging until it hit full, which is a completely reasonable number. This power pack is now 4-6 full charges for a modern smartphone, actual capacity!
Test #2 - Opus Analyzing Charger
This Opus analyzing charger has constantly surprised me with its results. Cells I thought were good have turned out to be garbage, and cells I thought were garbage have turned out to be workhorses. Science doesn't tell us how to live, but it can measure a battery's capacity like a boss.
These are two cells I pulled out at random and stuck in the charger, knowing it was going to be a long wait.
Test Results: Slot 1 was 3322 and Slot 2 was 3296. Not bad for their first charge cycle.
So, the Opus likes them.
These are the real deal. I started testing them immediately in case I would have to return them, but no need since that USB battery pack is now my precious, and I have the cells to build several more just like it. I have a 6x18650 DIY power bank coming within a week or so. Something that size should be fairly ridiculous with 6 of these bad boys in it.
Sure, there are about a million other USB power packs, but they almost universally lie about their capacity. Most give you the capacity that it would have if it had good cells in it like these, but they put varying degrees of awful Chinese cells in them, usually in the range of about 1,000 mAh each. Having a power pack with a real world capacity of about 13,000 mAh is about as good as you can get at any price.