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Anker335 Power Bank PowerCore 20K

Large power bank
20000mAh

£49.99View retailers

Test score

Lowest available price

£49.99Amazon Marketplace UK

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Anker says that its 335 PowerCore 20K has enough capacity to charge an iPhone 14 over four times with ‘blazing fast speeds’. Anker is a mainstay in this market, but to verify its claims independently, we’ve taken it to the test lab. Read our expert review to see if it’s the power bank you’ll want to buy.

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What's included?

What is it?
How easy is it to use?
How well does it perform?
Should I buy it?

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KEY TEST RESULTS
Performance
Ease of use
Features

Jun 2023First reviewed by Which?
Aug 2022Released

The overall Which? test score is made up of the following star ratings, all determined by our rigorous lab tests.

How we test portable power bank chargers

5 Mar 2024

Performance

Overall
Capacity - actual v claimed
Efficiency
Power bank charging time
Device charging time

How we test performance

How long does the power bank take to charge? How quickly will it charge your devices? And does it deliver on the amount of power that the manufacturer says it will?

Ease of use

Overall
Portability
Capacity and charging indicators
Sockets

How we test ease of use

Are the sockets well marked and far enough apart? Does the capacity indicator work properly? And how easy is it to carry around? We weight these results so that portability is more important in small power banks, and less important in large power banks

Features

How we test features

How many outputs does it have? Does it have any special features that let it charge faster? Does it have wireless? Can you charge this power bank and your devices at the same time?

General
Type	Large power bank
Claimed capacity	20000mAh
Width	8.4cm
length	16.5cm
Height	2.5cm
Weight	484g

Features
Pass through charging	No
Power delivery	No
Wireless charging	No
Display type	4 LED indicators show battery power level
Accessories included	Usb A to Usb C cable x1

Power
Power bank charging time
No. smart phone charges possible	4.6372561519827
No. Tablet charges possible	2.2459628863433

Connections
Input 1	Usb C
Input 1 specs	5Vdc - 3A9Vdc - 2A
Input 2	No
Input 2 specs	No
Input 3	No
Input 3 specs	No
Output 1	USB A
Output 1 specs	5Vdc - 3A9Vdc - 2A12Vdc - 1,5A
Output 2	USB A
Output 2 specs	5Vdc - 3A9Vdc - 2A12Vdc - 1,5A
Output 3	USB C
Output 3 specs	5Vdc - 3A9Vdc - 2,22A
Shared output	Yes
Max combined output	18W

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Amazon Marketplace UK
In Stock£49.99

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Anker335 Power Bank PowerCore 20K

Lowest available price