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EnergizerMax 20000mAh UE20058

Large power bank
20000mAh

£24.87View retailers

Test score

Lowest available prices

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We were eager to try out this large power bank from Energizer, one of the biggest names in batteries. Energizer says in can fully charge a smartphone up to six times – which would be impressive for a model of this size. Does it live up to its claims? Read our full Energizer UE 20058 20000mAh review to find out.

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cons

What's included?

What is it?
What’s it like to use?
How well does it perform?
Is there anything else I should know?
Should I buy it?

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KEY TEST RESULTS
Performance
Ease of use
Features

Jul 2023Last checked by Which?
Aug 2022First reviewed by Which?
Jan 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	7.1cm
length	14.8cm
Height	2.9cm
Weight	412g

Features
Pass through charging	No
Power delivery	No
Wireless charging	No
Display type	Digital display with range from 0 to 100%
Accessories included	USB A to Micro USB cable x1

Power
Power bank charging time
No. smart phone charges possible	4.1
No. Tablet charges possible	2.04

Connections
Input 1	Micro usb
Input 1 specs	5Vdc - 2A
Input 2	Usb C
Input 2 specs	5Vdc - 2A
Output 1	USB A
Output 1 specs	5Vdc - 2.1A
Output 2	USB A
Output 2 specs	5Vdc - 2.1A
Output 3	No
Output 3 specs	No
Shared output	Yes
Max combined output	10.5W

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EnergizerMax 20000mAh UE20058

Lowest available prices