Please check:

 ● Your phone is an iPhone with MagSafe (iPhone 12 series or later).

 ● Your protective case is less than 2mm thick.

 ● There are no metal accessories, credit cards, or pop sockets between your phone and the power bank.

 Additional information about wireless charging speeds:

 ● Wireless charging is not as fast as wired charging.

 ● Limiting the number of applications you have open simultaneously on your phone will improve charging speed.

 ● High temperatures will reduce charging speed and restrict power, which is something that happens during wireless charging.

 ● When your iPhone stops charging at 80%, it may be due to "Optimized Battery Charging". Please check whether turning it off helps. Click Settings > Battery > Battery Health > Turn off "Optimized Battery Charging". If you haven't enabled "Optimized Battery Charging", the issue is mostly caused by the iOS upgrade. Please upgrade or wait for the next system upgrade.

If you’re still having problems with the product, you can contact ESR Customer Support for further assistance. Make sure to briefly mention the tips you’ve already tried so that we can find a faster solution for you.

The 5,000mAh power bank is lightweight, which makes it easy to carry and can be used as a second battery to power up your phone. 

We recommend our 10,000mAh power bank if you're a heavy phone user.

● Operating temperature should be between 32°F to 95°F/0°C to 35°C.

● Do not expose power bank to rain, snow, or any humid environment.

● If the power bank expands or gets extremely hot, stop using immediately. Damaged batteries may exhibit unpredictable behavior resulting in fire, explosion, or risk of injury.

● Do not disassemble this power.

● Turn off the power bank when not in use.

The discrepancy between the nominal and rated capacities of a power bank, such as a 5,000mAh power bank displaying a typical rated capacity around 3,000mAh, can be attributed to two main factors: capacity conversion loss and circuit loss.

Capacity Conversion:

The 5,000mAh rating refers to the total charge capacity of the power bank's internal battery cells, which typically operate at a voltage of around 3.7V. However, the rated output capacity of the power bank is often calculated at a standard output voltage of 5V. Using the energy conservation formula (Energy in Watt-hours = Capacity in Ampere-hours × Voltage in Volts), we can calculate the adjusted capacity:

5Ah × 3.7V = 18.5Wh

18.5Wh / 5V = 3.7Ah = 3,700mAh

Circuit Loss:

To boost the voltage from 3.7V to 5V, power banks use a conversion circuit. This process incurs energy loss due to inefficiencies in the circuit, typically around 82% efficiency. This means that not all the stored energy can be efficiently converted and used at the higher voltage.

Calculation of Final Rated Capacity:

Given the efficiency and the adjusted capacity:

Rated Capacity = 3,700mAh × 0.82 = 3,034mAh

Thus, the effective rated capacity that can be used by devices is about 3,034mAh, which explains why a 5,000mAh power bank might typically display a rated capacity around 3,000mAh on its label.

If you have any further questions, feel free to contact ESR Customer Support for assistance.

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