Update: This popular Frontpage deal is available again with a new promo code.
B King via Amazon has
LISEN 5000mAh Qi2 Wireless 15W Ultra Slim MagSafe Power Bank w/ 22.5W USB-C & 1.6' USB-C to USB-C Cable (Ice Gray) on sale for $24.98 -
$7.99 off when you apply promo code
TCS6NMYT at checkout =
$16.99.
Shipping is free with Prime or on $35+ orders.
Thanks to Deal Hunter
Navy-Wife for posting this deal.
- Note: You must be logged in to apply promo codes; promo codes are typically for one-time use and don't always apply seamlessly. If you run into this issue, refresh the page, re-enter the code, or revisit the cart page.
Details:
- Ultra-slim Qi2 magnetic power bank: 0.3 inches thick, 5,000mAh capacity; Qi2-certified for efficient 15W wireless charging
- Fast charging: 15W wireless (up to 50% in 1 hour for iPhone 17); 22.5W wired; speed reduces after 75% charge
- Portable & lightweight: Thinner than iPhone 15; 12N strong magnets for secure snap-on fit; ideal for commuting, travel, classes, parties, concerts
- High safety & certifications: Lithium-polymer battery with NTC temperature control and overcharge protection; FCC, CE, RoHS, UL, PSE, Qi2 certified; no recalls or safety issues
- Compatibility note: Optimized for MagSafe iPhones (12–17 series); non-MagSafe cases may cause heating; avoid gaming while charging
- Package contents: 1× LISEN ultra-slim MagSafe power bank, 1× 1.6ft USB-C to USB-C cable
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Top Comments
tl;dr: The Wh rating provided on power banks is agnostic of the voltage and would be a better "apples to apple" comparison of power bank capacity than mAh ratings. Wireless charging is inefficient and compared to wired loses 25-50% capacity due to losses.
The details:
Specified mAh capacity refers how much power can be delivered at a certain current over the time that the battery has power. If this is not specified with a particular voltage is, it's referring to the voltage of the battery cells inside the power bank, which is why they specify at 3.6 V.
The voltage can be upconverted to a "standard" USB 5V but that reduces the mAh rating proportionally . I've looked at my Anker/Ravpower/Belkin/Inui/Baseus banks and they all specify at 3.6 V. Sometimes the conversion to 5V is also given but not usually.
Wh capacity of a battery pack takes the voltage into account, and is a "clearer" representation of power capacity.
As a second issue - wireless charging is intrinsically much less efficient than wired charging (even when wired, a "3000 mAh battery pack" may need 4000 mAh to charge it), and at best case scenario wireless charging only delivers 3/4 (compared to wired charging) of the power capacity to the charged unit, with the remain lost to heat and other conversion inefficiencies. Realistically with wireless charging even in best case scenarios a 3000 mAh phone battery may only be half charged by a 3000mAh power bank.
At worse (poor alignment, greater separation) it could be less than half of this.
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tl;dr: The Wh rating provided on power banks is agnostic of the voltage and would be a better "apples to apple" comparison of power bank capacity than mAh ratings. Wireless charging is inefficient and compared to wired loses 25-50% capacity due to losses.
The details:
Specified mAh capacity refers how much power can be delivered at a certain current over the time that the battery has power. If this is not specified with a particular voltage is, it's referring to the voltage of the battery cells inside the power bank, which is why they specify at 3.6 V.
The voltage can be upconverted to a "standard" USB 5V but that reduces the mAh rating proportionally . I've looked at my Anker/Ravpower/Belkin/Inui/Baseus banks and they all specify at 3.6 V. Sometimes the conversion to 5V is also given but not usually.
Wh capacity of a battery pack takes the voltage into account, and is a "clearer" representation of power capacity.
As a second issue - wireless charging is intrinsically much less efficient than wired charging (even when wired, a "3000 mAh battery pack" may need 4000 mAh to charge it), and at best case scenario wireless charging only delivers 3/4 (compared to wired charging) of the power capacity to the charged unit, with the remain lost to heat and other conversion inefficiencies. Realistically with wireless charging even in best case scenarios a 3000 mAh phone battery may only be half charged by a 3000mAh power bank.
At worse (poor alignment, greater separation) it could be less than half of this.
Our community has rated this post as helpful. If you agree, why not thank NateRules
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Thanks for pointing this out. would rather spend a few dollars more for 5000mAH
Our community has rated this post as helpful. If you agree, why not thank Backhome77
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I prefer the Anker MagGo ultra slim which is roughly the same thickness and weight but feels smaller because of a more aggressive taper on the edges.
Xiaomi has released a slightly thinner and lighter silicon carbon portable battery bank. Internationally it's about 70 US dollars and that would be my next pick but it is much more expensive.
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