Anker 621 Magnetic Portable Charger (MagGo), 5,000mAh Wireless Power Bank with USB-C Cable, Magsafe-Compatible Battery Pack for iPhone 16/15/14/13/12 Series

This was my first Magsafe battery. I had some older Qi wireless chargers and was familiar with heating issues. But these were older and lower power. Without the Magsafe feature, they were finicky and fussy and didn't properly fit around camera lens protrusions. I barely used these devices. This Anker 621 has a lot of promise. The Magsafe feature locks tight and the dimensions do not interfere with the camera protrusions, even with a case on the phone. It's compact and slim, and most importantly, does not require wires. It can be easily carried in a backpack or pocket without an accessory bag for wires and cables. When I first unpacked the battery, I fully charged with with a USB-C PD charger. It charged at 1A/5V. I used it to inductively charge my iPhone 14 Pro intermittently over the next few days. After about 10% charge, I determined the heat buildup to be intolerable. Therefore, I only used the pack intermittently. That worked fine for me over several days. When the battery was empty, it took 20Wh to fully charge. The battery was advertised for 5000mAh, which is impossible to measure without disassembling the unit. However, we can calculate 20Wh / 5V / 0.9 = 4400mAh (where 0.9 is the efficiency of the voltage converter for USB). This is below advertised capacity, but there’s a lot of assumptions in the conversion. Then I used a USB-C cable to charge my iPad Mini. It transferred 14.8Wh at about 9 Watts before exhausting. The round-trip efficiency was high, because recharging took 14.8Wh to fully recharge. I suspect I didn’t get the full 20Wh capacity with the iPad because the higher charge demand choked the battery before it could get fully empty. Using the inductive charge mode, both devices get hot relatively quickly. The switching power electronics get particularly hot. I can easily feel where the transistor is located beneath the plastic shell. The inductive transmitter loop gets warm on the battery and the receiver loop gets warm on the phone. Lithium-ion batteries degrade proportionally to temperature (the Arrhenius relationship), accelerating +25% degradation rate for every 10C, this is bad for the phone. In summary, • The battery delivers 20Wh of energy. If using inductive (Qi and Magsafe), much of the energy is converted to heat, so perhaps only 10-15Wh is actually delivered to the battery. • If using high-current devices using a charge cable, such as an iPad, the high current chokes the battery a bit early, stopping at 15Wh. • My back-of-the-envelope calculation shows 4400mAh vs. rated 5000mAh. I suspect the battery is not delivering rated capacity. Anker should be rating these batteries in Joules (watt-hours) instead of Coulombs (ampere-hours). • Inductive charging is inefficient, losing a quarter to half of energy to heat. This is not Anker’s fault but a result of real-world physics. With my iPhone 14 Pro, I saw about 10C rise per 10% of battery charge. I never let it progress beyond this point. • Lithium-ion batteries accelerate aging degradation due to the Arrhenius relationship about +25% per 10C temperature rise. Therefore, prolonged use of inductive charging will ultimately age your battery prematurely. • This battery is very worthwhile because I don’t have to carry an accessory kit with wires to use. Just slap it on the back of the phone and go. Plus, if frees the connector to use with wired headsets when using.

UPDATE 3/11/2026 - Anker absolutely honored their commitment to their product and issued me a replacement. They were quick to respond and to mitigate the issue I had with their product. Thank you ANKER!! I’m a huge Anker fan and a loyal consumer of their products, so this is the first time I’ve encountered an issue with one of their products. The charging itself works fine, the problem is that the magnetic charger gets very hot, which disrupts charging until the temperature drops. I have another brand with the same specs that doesn’t have this issue.​​​​​​​​​​​​​​​​

I’ve been using this Anker charger for a few weeks now and it’s been great. It charges my devices quickly and feels really solid and well-built. I also like how compact it is, making it easy to carry around. Definitely a reliable option if you need a fast and dependable charger.

Update: customer service provided me a replacement since the one I got was not working properly. I was expecting more from anker. I bought another one that was smaller and cheaper that performed better than this one. It gave me only 33% of charge in 2 hours once and 40% in 2h30 another time. It is ok to have for emergencies, the magnet is strong and is lightweight but for the price there’s better options out there.

Bought for my husband and he loves it. Easy to use / keep charged. Great price for a very reliable product.

This battery feels great to the touch, it's on the slimmer side, and the MagSafe isn't that bad, I got to give it that, but other than that, it's not worth your $40 dollars. The battery has a small capacity of 5,000mAh, which makes it die quickly, and it charges very slowly, delivering only 7.5 watts to your phone via MagSafe, taking up to 3 hours to fully charge. So if you are out and about, like most of us, and use your phone for a good amount of time, there's a good chance it won't fully charge while you are using it. Which is disappointing considering that Anker was supposed to be a good brand with more quality. I just think there are so many better Magnetic Portable chargers out there for much cheaper, offering double battery life and double charging speeds, all for less than this Anker. I feel disappointed, but I feel so much better about a $20 one I found online.

So handy to use if you forget your charging cord..it seems to charge phone quickly..you do have to charge the portable charger between each phnoe charging..for me it’s not a big deal..

Lo compré para mi mujer y está muy contenta con la batería externa. Trae suficiente carga para recargar su iPhone una vez (y sobrarle algo). Al ser pequeño y con MagSafe, pues cumple con todo. Buena calidad de construcción

Nice and small, does only give around one full charge and the phone tends to get fairly hot though. Magnets are plenty strong, certainly wouldn’t drop off but it can rotate on the phone if it’s in your pocket or something. Feels decent quality too, doesn’t feel like it’d break easy

Product is light weight and slimmest powerbank in the market. material feels very premium. Magnet has good power to hold the mobile.

Amazing and I love the colour. I can even use it as a wire charger for my AirPods and not worry about it sliding off the patch it has magnets

Rekomenduję , super