With the increasing popularity of mobile devices, mobile power has become an indispensable part of our daily life. There are a wide range of power bank products, including large-capacity, high-power outdoor dedicated power banks, as well as small, lightweight, and suitable for daily carrying of mini power banks. In addition, with the advancement of technology, wireless charging power banks, multi-interface mobile power supplies, etc., have also appeared, meeting the diversified needs of different consumers.
In this issue, Xiaobian will take you to understand the definition, terminology and quality points of mobile power supply.
Note: The content is based on GB/T 35590-2017
Information Technology - General Specification for Mobile Power Supplies for Portable Digital Devices
Key words in this issue: key points of mobile power quality
01 Definition of power bank and related terms
Power bank, which is a non-stationary power supply system that can provide stable DC output by a combination of batteries or battery packs, corresponding circuits and shells, and does not exceed 18kg of power supply that can be carried by users.
| Some terms related to power banks | ||
| Chinese and English names | definition | units, etc |
| Rated input voltage rated input voltage | The value of the input voltage as determined by the manufacturer's trademark | Expressed in Uin in volts (V) |
| Rated input current rated input current | The value of the input current as determined by the manufacturer's mark | Expressed in Iin in amps (A) or milliamps (mA) |
| Rated output voltage rated output voltage | The output voltage value determined by the manufacturer's trademark | Expressed in Uout in volts (V) |
| Rated output current rated output current | The sum of the output currents of each port of the same output voltage specified by the manufacturer | Expressed in Iout in amps (A) or milliamps (mA) |
| Effective output capacity effective output capacity | The fully charged power bank is discharged to the cut-off according to the rated output current, and the effective discharge capacity of the actual output to the external load | Measured in ampere-hours (A·h) or milliampere-hours (mA·h) |
| Rated capacity rated capacity | The effective discharge capacity of the power bank as determined by the manufacturer's label | Expressed in C in ampere-hours (A·h) or milliampere-hours (mA·h) |
| Battery or battery rated energy cell or battery rated energy | The rated energy of the battery or battery used in the power bank, that is, the rated capacity of the battery or battery multiplied by the rated voltage of the battery or battery pack | Measured in watt-hours (W·h) or milliwatt-hours (mW·h) |
| Effective energy output effective output energy | A fully charged power bank is discharged to the cut-off at the rated output voltage according to the rated output current, and the effective discharge energy is actually output to the external load | Measured in watt-hours (W·h) or milliwatt-hours (mW·h) |
| Conversion efficiency conversion efficiency | According to the charging and discharging conditions specified in the standard, the ratio of the effective output energy of the power bank to the rated energy of the battery or battery pack | / |
| Cycle life cycle life | The number of charging and discharging cycles that can be performed before the effective output capacity of the power bank is less than 60% of its rated capacity | / |
| Capacity retention capacity capacity retention | It is stored for a period of time at the specified temperature and time, and the effective output capacity of the power bank is realized | / |
| Rated capacity rated capacity | The number of charging and discharging cycles that can be performed before the effective output capacity of the power bank is less than 60% of its rated capacity | / |
| Leakage ileakage | Visible leakage of liquid electrolytes | / |
| Discouraged venting | When the internal pressure in the power bank increases, the gas is released through a pre-designed explosion-proof device | / |
| rupture Break up | Mechanical damage to the power bank housing due to internal or external factors, resulting in exposure or spillage of internal substances, but no ejection | / |
| Ignition fire | The power bank has a visible flame | / |
| explode explosion | The power bank's shell cracked violently, causing the main ingredient to eject out | / |
02 Power Bank Quality Requirements
The quality requirements of the mobile power supply include appearance, interface, security performance, etc. The details are as follows:
Appearance and logo of the power bank
The appearance should meet the following requirements:
- The surface is clean, no obvious deformation, no mechanical damage, and no rust at the interface contacts;
- There is a necessary mobile power bank logo on the surface, and the identification is clear;
- The output and input interfaces should be clearly marked for easy connection;
- Interfaces, buttons, battery level indicators (or lights) warnings, etc. are clearly marked.
The mobile power supply body should have the following logos:
- Name and model of the power bank;
- the manufacturer's name, trademark or identifying mark;
- Rated input voltage and current, rated output voltage and current;
- Rated capacity;
- the type and rated energy of the battery or battery;
- For multiple output ports, the total current value of the output voltage of the same grade should be identified, and the rated output voltage and current of each output port should be marked near each output port.
The interface of the power bank
The output and input interfaces should be clearly specified in the mobile power manual, and the shape should be upright, regular, without damage and deformation, and have an anti-polarity reverse connection design, and should be able to input and output normally after plugging.
The electrical properties of the power bank
Effective output capacity
- Effective output capacity at room temperature: effective output capacity, power bank, and
- Effective output capacity at low temperature: effective output capacity should be, mobile power supply, and;
- Effective output capacity at high temperature: The effective output capacity should be, power bank, and.
capacity retention capacity, etc
- Capacity retention capacity: The effective output capacity of the power bank should be
- Cycle life: Power bank cycle
- Conversion efficiency: The conversion efficiency of the power bank shall conform to the express value of the manufacturer's instructions for the use of the power bank, if not expressly stated
- Output Voltage: Actual Output Voltage;
- Ripple and Noise: Output voltage ripple and noise (peak-to-peak).
Power suitability in the state of charge
- For AC-powered power banks,;
- For DC-powered power banks,.
Security protection features
- Overcharge protection: In the case of overcharging, the power bank should start the protection, and should not explode, deflate, fire, or leak;
- Short-circuit protection: In the case of short-circuit, the power supply should be activated for protection, and should not explode, not deflated, not fired, and not leaking;
- Overload protection: In the case of overload, the power supply should not explode, not deflat, not fire, and not leak;
- Misoperation: In the case of misoperation, the power bank should not explode, not deflat, not catch fire, and not leak.
safety
Some of the safety and quality requirements are as follows:
- Electrical safety of the whole machine: The safety of the whole mobile power supply should meet the corresponding requirements stipulated in GB4943.1-2011 or its alternative standards;
- Safety of batteries and battery packs: The lithium-ion batteries or battery packs that make up the power bank shall meet the corresponding requirements specified in the GB31241, and the nickel-metal hydride or nickel-cadmium batteries or battery packs that make up the power bank shall meet the corresponding requirements specified in GB/T28164 (Note: The relevant product parameters and technical specifications of the constituent batteries or batteries required for the tests specified in this article shall be provided by the manufacturer);
- Material flame retardant: The flame retardant grade of the shell, printed board and insulating material of the mobile power supply shall not be lower than the flame retardant requirements of V-1 level. The internal wires of the power bank should meet the requirements of the GB31241;
- Stress relief: The structure of the molded or injection-molded thermoplastic enclosure should be such that any shrinkage or deformation of the enclosure material will not expose the internal components when the internal stresses generated by the molding or injection molding are released;
- High-temperature charging and discharging: In the case of high-temperature charging and discharging, the mobile power supply should not explode, not deflat, not catch fire, and not leak.
Environmental adaptability
- Constant damp heat: During the constant damp heat test, there should be no explosion, no outgas, no fire, and no leakage. After the test, there should be no obvious deformation and rust in the appearance, and the mobile power supply should be able to work normally in accordance with the functions specified in the manual;
- Temperature cycle: During the temperature cycle test, there should be no explosion, no outgassing, no fire, and no leakage. After the test, there should be no obvious deformation and leakage, no crackage in the assembly, no mass loss, no breakage, and the mobile power supply should be able to work normally in accordance with the functions specified in the manual;
- Vibration: During the vibration test, there should be no explosion, no deflating, no fire, and no leakage. After the test, the mobile power supply should be able to work normally in accordance with the functions specified in the manual, and the appearance should be no obvious deformation;
- Collision: There should be no explosion and no fire during the crash test. After the test, the mobile power supply should be able to work normally in accordance with the functions specified in the manual;
- Free fall: During the free fall test, it should not explode, deflate, fire, leak, or rupture to cause safety hazards. After the test, the power bank should be able to work normally according to the functions specified in the manual, and the measured output voltage should be within the 5% deviation range of Uout±;
- The content of restricted substances: It shall meet the requirements of GBT 26572, that is, the content of lead, mercury, hexavalent chromium, polybrominated biphenyls and polybrominated diphenyl ethers shall not exceed 0.1% (mass fraction), and the content of cadmium shall not exceed 0.01% (mass fraction) in each homogeneous material constituting electrical and electronic products.
In the next issue, we will take you to understand some common inspection points and methods in the inspection of mobile power supplies. For more inspection knowledge training, you can also download TradeAider QC APP to register and learn.