I tore apart a 9,000,000mAh power bank from eBay to find out the truth – here’s what’s inside

A power bank with a whopping 9 million milliamp hours (mAh) that fits in the palm of your hand, all for just over $10, sounds pretty cool, doesn’t it? Well, you know what they say.

A reader brought this list to my attention questioning the validity of such bold claims. Although I had a lot of doubts, I decided to investigate further. Of course, this is all in the name of science.

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First, let’s put the 9 million mAh claim into perspective. $150 Anker PowerCore 24K It has a capacity of 24,000 mAh, and is a fairly large power bank, weighing in at 1.3 pounds. To get a capacity of 9 million mAh, I would need to spend over $35,000 on 375 PowerCore 24K power banks, and that’s definitely not something I’d want to carry around with me – nor would it fit in the palm of my hand.

So, I ordered one of these supposedly large capacity power banks and waited a few days for delivery.

Here’s what I received:

Surprisingly, the packaging made no concrete claims about the promise, but the potential was still unrealized. Additionally, the numerous typographical errors on the package do not inspire confidence in the product.

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The inactive state of the power bank upon arrival also did not improve my first impression. Worse, despite my attempts to charge it, nothing worked. It was completely unresponsive out of the box.

Maybe I can come back to “warranty”. I doubt it.

Now it was time to turn the dice and take it apart to see what was inside. At this point, my money was on even more disappointment. Since I was looking for a power bank, I didn’t want to use my trusty metal spudgerSo instead, I turned to a safe plastic tools.

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Then, to both my shock and surprise, while I was peeking inside the power bank, the power bank glowed for a few seconds.

After a little force – sometimes an unreasonable amount – the case opened up and I could see what the problem was. One wire of the battery was disconnected. Not only did this explain why it was not working, but it also posed a risk of short-circuiting and even causing a fire.

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I took a closer look at the batteries.

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They were all no-name 18650 lithium-ion cells, and I measured their capacity at about 2,000 mAh. I suspect these may be old “recycled” cells or possibly seconds, as I would expect even a cheap 18650 cell to have a capacity of around 2,300 mAh. This means that the capacity of the entire pack was 6,000 mAh, much less than the advertised 9,000,000 mAh.

Now, to be honest, this is ultimately what I was expecting.

Exaggerated claims lead buyers to purchase poor quality power banks manufactured inefficiently from cheap parts. If you’re looking for a cheap power bank, I’d say spend the extra ten bucks shopping around and get this for yourself. Baseus 10000mAh for $20. This way, you’re getting a good quality power bank that delivers on its promises, will serve you for many years, and won’t be a potential fire hazard.