Another high-capacity battery: Sanyo NCR18650GA

I've reviewed a lot of batteries, including high-capacity models, but one interesting "fellow" had never been tested. Thanks to one of my regular readers, I now have one in my hands, and today I'll be taking a look at the Sanyo NCR18650GA.

I wasn't planning to test any more batteries this year, but circumstances changed and I had to dust off my electronic load again :)
First, I'd like to thank Roman for providing the batteries for testing. There are actually three types, two of them in sets of four. It's worth noting right away that these batteries aren't new—not because they've been used for a long time, but because they were bought a while ago and spent most of that time just "sitting on a shelf." That might actually make this even more interesting.


So, the Sanyo NCR18650GA. The color is classic for batteries made by Sanyo, although Sanyo is now a division of Panasonic. In practice, that hasn't affected the quality or even the appearance—and why would it?


What makes these batteries noteworthy?
First, they have a relatively high capacity of 3350 mAh. Just as important, though, is their maximum continuous discharge current of 10 A. That's not very common among high-capacity batteries; this figure is usually limited to 6.5–6.8 A (2C) or 8 A (Samsung 35E).


I picked two of the four batteries I received for testing.

According to the 6708 code, the batteries were manufactured on July 8, 2016. The marking is barely visible, but it looks like it was applied with a laser rather than printed with ink. The positive terminal protrudes noticeably beyond the casing. The matrix code can be used to check for counterfeits; it should be unique to each battery.


Dimensions and weight.


The person who sent me the batteries said they'd been tested and charged, then put aside. So they arrived with a charge of about 4.11 V, which is good for long-term storage.
A "conditioning" run with a regular charger showed a capacity of almost 3500 mAh.


High-capacity batteries often have a maximum charging current of 0.5C, and this model is no exception. A full charge takes 2 hours and 40 minutes, which is quite a long time.


The datasheet includes discharge curves at 2, 4, 6, 8, and 10 A, which don't quite match the test conditions I usually use. In practice, though, the differences aren't that significant, so I made no exception for these batteries and tested them at 0.2C, 0.5C, 1C, 2C, and 10 A. Testing was done with an EBC-A10H electronic load.


The discharge curve differs slightly from the one shown above. The differences show up at the highest discharge currents (2C and 10 A); I suspect the batteries' age—three years—had an effect after all.


The temperature was also slightly higher than stated in the datasheet. For example, at 10 A, the datasheet gives about 61–62°C, while the actual temperature was closer to 70°C.
Results at 0.2C (6.7 A) and 10 A.


The second battery behaved identically.



The datasheet also includes a discharge curve at different ambient temperatures. It clearly shows something I sometimes mention in my reviews: the battery's self-heating effect, which is especially pronounced at low temperatures. The voltage drops at first, then starts to rise. This effect partly causes the discharge curves to "cross" at high currents, where the delivered capacity in mAh can even exceed the capacity at a lower discharge current.


The test showed that the batteries have very similar characteristics. As an additional comparison, I tested them at 0.2C and 10 A: one battery is shown in red, the other in blue.


The datasheet also includes a graph showing how capacity changes with the number of full cycles. Interestingly, capacity drops more rapidly during the first two or three hundred cycles.


Resistance as received, after "conditioning," and after all the tests. You can see that resistance increased as testing progressed, and did so in exactly the same way for both samples.


And, of course, a comparison graph at 0.2C and the maximum current, which for these batteries is 10 A. The graph and the testing itself will be added to the roundup later.
Samsung INR18650-35E - red
LG INR18650-MH1 - orange
LG INR18650-MJ1 - yellow
LG INR18650-M36 - green
Panasonic NCR18650G - light blue
Panasonic NCR18650BD - blue
Sanyo NCR18650GA - purple

At 0.2C, the batteries reviewed here are somewhere in the middle of the pack, with both higher- and lower-capacity models.


At 10 A, the list of batteries and the currents used to test them is shown below the graph. In the 10 A ranking, this battery was beaten only by the LG-MJ1, since the batteries ahead of it were tested at lower currents (though the maximum for those models). Its closest competitor is the Samsung 35E, which could have beaten the Sanyo NCR18650GA, but its maximum current is 8 A and the discharge cutoff is 2.65 V.


To sum up, these batteries are quite interesting and can be recommended for use, especially since they are fairly affordable. There is one catch, though: they are very often counterfeited. If you buy a fake, you won't get the results shown above—and even if you do, they probably won't last long. These batteries are available on AliExpress; they might even be genuine, but as they say, there's no guarantee.

Later, I want to run a shortened test on the second pair of batteries, but judging by how consistent the results were for the first pair, I think everything will be fine.

That's all. I hope you found this useful :)