Tested by the State Grid Metering Center! YMIN Supercapacitors Deliver Short-Time Backup Power for Smart Grid Systems

State Grid’s Response: The Q/GDW 11845—2018 Standard

The State Grid Corporation of China (State Grid) imposes exceptionally rigorous requirements on the components used in equipment connected to its grid. In electricity metering devices, supercapacitors play a critical role by providing backup power during sudden power outages, thereby ensuring the secure storage of data. Compared to traditional backup power sources, supercapacitors offer distinct advantages—such as the ability to deliver high peak power instantaneously, the capacity to operate across a wide temperature range, a long service life, and superior safety and reliability—making them the ideal choice for backup power in electricity metering equipment.

To address this, the State Grid established the technical specification "Q/GDW 11845—2018: Technical Specifications for Supercapacitors Used in Electricity Metering Equipment." This standard mandates comprehensive, extreme-condition testing covering the electrical performance, mechanical properties, environmental adaptability, and safety/reliability (including resistance to explosion and puncture) of supercapacitors.

Passing the testing conducted by the State Grid Metering Center serves as a guarantee that a product maintains high levels of reliability and safety even in extreme environments, making it the most trusted choice for power equipment manufacturers.

Successfully Passed State Grid Metering Center Testing—All Evaluated Criteria Met!

In compliance with this standard, the SDL(G) and SDM(G) series supercapacitors from Yongming Electronics have successfully passed testing by the State Grid Metering Center Co., Ltd. All technical indicators for the submitted samples met the requirements stipulated in the Q/GDW 11845—2018 standard.

Figure 1. Physical image of the SDL 10F 2.7V

Figure 2. Physical image of the SDM 1.5F 5.5V unit

Figure 3: SDM State Grid Metrology Testing Report

This product offers core advantages in safety, weather resistance, self-discharge performance, and solderability:

Exceptional Safety and Robustness

The product has successfully passed destructive safety tests, including crushing, nail penetration, thermal abuse, and abnormal charging. In all four tests, the results showed "no explosion, no fire," meeting the requirements of the Q/GDW 11845—2018 standard. This helps electricity meter manufacturers mitigate fire risks during safety testing and extreme failure scenarios.

Superior Weather Resistance

The product has undergone rigorous testing, including thermal shock, steady-state damp heat, and high/low-temperature storage and performance tests. Capacitance change rates remained within -10% after thermal shock, -30% after steady-state damp heat, and -30% after high-temperature storage. With stable internal resistance and no leakage or damage, the product is well-suited for the high/low-temperature and humid environments encountered by outdoor electricity meters and data concentrators, preventing insufficient backup power caused by capacity degradation.

Ultra-Low Self-Discharge for Long-Term Energy Storage

The product demonstrates excellent self-discharge performance (≥80% of rated voltage). Measured voltages after the self-discharge period were 4.80V and 4.74V (against a rated voltage of 5.5V, where 80% of the rated voltage is 4.4V). Combined with a low leakage current (≤20μA; actual measured values: 6.4μA and 2.3μA), the product retains its voltage even after long-term storage, ensuring reliable backup power during outages and reducing the need for on-site maintenance or battery replacement.

Excellent Solderability

The product meets all requirements for resistance to soldering heat and solderability. After exposure to soldering heat, the capacitance change rate is 0.0%. Following solderability testing, the surface exhibits a smooth, bright solder coating. Performance remains stable after reflow soldering, making the product ideal for automated production lines and helping to improve the first-pass yield.

Wide-Ranging Applications: Compact Size, High Energy

Currently, Yongming supercapacitors are widely used in the following areas:

Smart Grid and Electricity Metering

Used in equipment such as single-phase smart electricity meters and Type I data concentrators. In the event of a sudden power grid outage, it provides short-term backup power to clock chips and main control chips, ensuring that records of power-loss events and critical data are securely stored and preserved.

Distribution Automation and Communication Terminals

Used in integrated smart communication units (SCUs), feeder/distribution terminal units (FTU/DTUs), and high-speed power line carrier (HPLC) modules. It supplies peak power during voltage dips or power failures, enabling communication modules to complete a final data transmission—preventing data loss or the disconnection of network nodes.

Smart Switches and Low-Voltage Electrical Equipment

Used in low-voltage terminal units (LTUs), molded-case circuit breakers (MCCBs), and smart miniature circuit breakers (MCBs). It serves as a backup power source for tripping mechanisms, ensuring reliable switch operation during extreme fault conditions and enhancing the safety of the power distribution system.

Selection Matrix

The following models are provided for reference; you may select the appropriate unit based on your equipment’s supply voltage, installation dimensions, and backup power requirements.

Choosing Yongming supercapacitors means choosing stable, long-lasting energy support.