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

The color matches the new iPhone 17 in lavender. The charging is ok, it makes the phone pretty warm and is only good for 1 full charge or several partial charges. It's small, light and works in a pinch which is why we have it.

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.

Durable I’ve had it for 2 years and it still works great, it’s portable, it kinda gets warm when in use.

This battery has honestly changed the way I travel. It only charges my battery up to 70% but for me that’s more than enough. The slim design makes it easy to carry to the point I don’t notice I have it in my pocket. I’m giving it 4 stars only because the battery does get hot but besides that I like it

Before ordering I had struggled to get answers to some basic questions about how this battery works, so now that I have it in hand I'm hoping these tips are useful: - The battery charges the phone wirelessly when the battery is attached to the phone magnetically and turned on. - While the phone and battery are attached the power moves in only one direction from the battery to the phone. The battery doesn't charge wirelessly when attached to a phone even if the phone is plugged in. - The battery must be charged independently of the phone. It can be charged either by plugging a USB-C cable into it directly or by putting it on any wireless charging pad. - You CAN plug a USB-C cable directly into the battery to charge it while it's attached to the phone and while it's actively charging the phone. It's possible this isn't recommended, but it does appear to work. - The battery blocks the phone's Magsafe charging area while it's attached to the phone, but the phone can still be charged directly via USB-C with the battery attached. - The battery can't be charged wirelessly while attached to a phone since it must be placed Magsafe-down onto a wireless charging pad. - The battery just barely fits into the space between the camera protection area and the bottom edge of a standard phone case with very little room to spare. The magnets are very effective, though, and it stays firmly attached to the phone. - A short USB-C cable is provided, but you need to provide a USB AC charger or wireless charging pad.

This works well, it’s compact and fits in my pocket, which is what I wanted, but it really doesn’t charge as well as the bigger corded ones. I would probably still buy it again. It also only barely charges my iPhone 14 Pro, a full charge. Convenient for walking around listening to my podcast.

Acquistata per avere un po’ di batteria extra durante la giornata e devo dire che fa esattamente quello per cui è pensata. Si attacca bene al retro dell’iPhone, il magnete è solido e non si stacca facilmente nemmeno mentre lo si usa. Le dimensioni sono contenute e non dà troppo fastidio in tasca o in mano. I 5000 mAh non fanno miracoli, ma sono più che sufficienti per una ricarica di emergenza o per arrivare tranquillamente a fine giornata. La ricarica è stabile e non ho riscontrato problemi particolari. Apprezzato anche il cavo USB-C incluso, così non serve portarsi dietro altro. Come spesso succede con la ricarica magnetica scalda un po’, ma nulla di anomalo. Nel complesso un buon prodotto, ben costruito e pratico, soprattutto se si cerca qualcosa di compatto da usare al volo senza cavi.

Slim, with a good magnet and the charging goes through my thicker (two-layered) protective case which my other one doesn’t. Very satisfied!

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

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

This is my 2nd one of these and they work perfectly: They can charge an iPhone 16 pro to about 80% from flat. Slim and easy to handle while attached. The MagSafe connection is strong, and they recharge quickly on a 20w+ usbc charger.