Are Anker’s PowerCores the best power banks you can buy? To be honest. I have now serious doubts about the quality of Anker power banks in Asia. I bought an ANKER PowerCore 10400mAh Power Bank two years ago from the official dealer in Vietnam. But in the second year, it started to show big problems. So I decided to tear the PowerCore down to have a look inside. It was not what I was expecting.  

My iPhone 7 is an energy-hungry monster. It demands to be charged two or three times a day. On my trips, I want a reliable power bank for the consumption needs of my iPhone. I read many times on the internet that Anker makes the best power banks. Lucky me that the official Anker dealer in Saigon was offering a 10400Mah PowerCore for a discount. If it’s the official dealer then I can be 99 percent sure the power bank isn’t a fake. I ordered one and used it right away on my one week-long trip to the gorgeous beaches of Vietnam. 

When I’m not traveling the PowerCore is mostly in use by my girlfriend. She alternates the use with the two Xiaomi power banks we own. Gradually she was abandoning the use of PowerCore in favor of Xiaomi’s. They lasted longer. The moments I needed the PowerCore it was often empty. My girlfriend assures me that after every use she connected the Anker to the charger. 

Time to do a capacity test. I use a USB meter in combination with a USB load. Power Bank manufacturers are advising against this method. However, in my judgment, this is a reliable method to test a power bank. I discharge the power bank with two amperes. The minimum that every power bank should deliver. If your power bank can’t do this then something is wrong. I don’t have a picture of the test with the Anker, but I can assure you that it was around 3000Mah. Way down south the given specifications. My girlfriend’s Xiaomi 10040 is still going strong. After the capacity test, the Xiaomi outputted around 6500Mah. She bought that power bank four/five years ago (She can’t remember when exactly).

Why is the Anker losing its capacity this quickly and is Xiaomi still in its giving capacity range? If I google Xiaomi teardowns I can see that they are using LG lithium cells. Sounds good. The Anker teardowns show Panasonic lithium cells. That also sounds good. 

The total capacity of the Anker is now too low to be used on a trip. Additionally, the power bank was already out of its warranty term. So I decided to open the power bank and to test the cells individually. 

In Saigon, I hunt for second-hand notebook battery packs. The cells inside I scavenge for my projects. I have a test method that I discharge them with 0,5 A to measure the capacity. Every cell that’s above 2000Mah I will keep, if the cell is under the 2000Mah, I bring them to the recycling center. On some days I’m lucky and I find for 1 dollar eight good cells. Sometimes I’m unlucky and I have eight worn-out cells. The same method I will use to test the four cells in the Anker Powercore 10400.

With the help of a phone pry tool, I opened the Anker. I have always thought that Anker uses cells from famous brands like LG, Sony, Samsung, or Panasonic. But I never heard of Cham Batteries from China. In my Asian Anker, PowerCore 10400 power Bank were four CMICR18650F8 Li-ion 18650 cells. 

After I tested the four batteries I have to say that I’m disappointed. This is not near the specification of 2600 Mah that the batteries are rated. I understand that batteries will lose their capacity over time and by usage. But a massive drop of more than 50 percent for a power bank that is used normally. With a phone, I can understand this behavior. That battery is discharged and charged every day. But after two years I always had around 80 percent of capacity. My phones have never reached more than 50 percent loss. 

As a reference, I also discharged a 30 months old 3400 Mah li-ion I use regularly in my Nitecore flashlight. The battery tested with a capacity of 3100 Mah. Specification versus reality is 91 percent of capacity. Impressive.

I don’t want to attack Anker. They make beautiful products. I love my Anker products. I own a Bluetooth speaker, cables, wireless charger, and a 30-watt USB-c charger. It’s just hard to swallow that my “quality” power bank failed this quickly because of the use, for my knowledge, unknown Chinese battery brand. Maybe the rumors are true and manufacturers make inferior products for the Asian en African market. Maybe the Powercore for the ‘western’ market has quality brand li-ion cells. But in conclusion I have a crappy Anker Powercore 10400 power bank.