Category: Arictern Energy

Safety Precautions for Battery Energy Storage Systems (BESS)

To ensure the safe operation and maintenance of Battery Energy Storage Systems, all personnel must strictly adhere to the following safety precautions:

1. Qualified Personnel Only

Only operators with relevant professional qualifications or those who have received specialized training in electrical equipment installation and commissioning are permitted to operate the system.

2. Familiarity with User Manual

Operators must thoroughly understand and follow the product’s User Manual to ensure correct handling and maintenance.

3. Emergency Preparedness

Operators should be trained to respond quickly and effectively to any hazardous or unexpected situations during installation or commissioning. Personal protective equipment (PPE) must be worn at all times during maintenance activities.

4. Use of Insulated Tools

All metal tools used during maintenance must be properly insulated to prevent accidental electrical contact.

5. Safe Module Replacement

When replacing battery modules, improper handling can lead to dropping hazards. Personnel must wear high-strength, safety-rated protective footwear to prevent injury.

6. Restricted Access to Battery Cells

Untrained or unauthorized personnel must not open battery cells. The internal electrolyte contains corrosive and hazardous substances that can harm skin and eyes.

7. Do Not Tamper with Warning Labels

System warning labels provide essential safety instructions. These labels must remain intact and must not be removed or damaged.

8. Two-Person Operations

All work inside the system must be conducted by at least two individuals. Each person must wear appropriate PPE, including insulated gloves and shoes.

9. No Open Flames or Smoking

Smoking or any open flames are strictly prohibited within or near the system. Before handling any DC components (e.g., battery modules or busbars), verify that they are properly
insulated from the system.

10. Long-Term Storage Considerations

Leaving the battery idle for extended periods can degrade its performance and lifespan. If the system is to be shut down for 3 months or longer, disconnect all electrical connections and ensure the battery retains some charge.

11. Emergency Stop Access

An emergency stop (E-stop) button must be easily accessible for immediate system shutdown during critical situations.

12. Restricted Access Control

Only authorized personnel should be allowed into the battery container. Access control systems and entry logs must be implemented to prevent unauthorized entry.

13. Proper Ventilation

Ensure that HVAC and ventilation systems are functional at all times to avoid thermal buildup and overheating.

14. Regular Safety Training

Conduct regular safety drills and refresher training for all operators to enhance readiness in the event of fire, electrical shock, or chemical exposure..

15. Use Compatible Chargers

Only chargers specifically designed for the battery’s chemistry should be used to prevent charging hazards or battery damage.

16. Maintain Safe Spacing

Maintain a minimum distance of 3 meters between two battery containers to prevent fire spread and allow safe access.

17. Standard-Compliant Grounding

Ensure that all BESS equipment grounding complies with relevant electrical safety standards.

What Is Calendar Aging?

Calendar aging refers to the deterioration of battery components due to chemical reactions that occur over time, independent of charge-discharge cycles.

Calendar aging significantly impacts Battery Energy Storage Systems (BESS) by causing capacity degradation and increased internal resistance over time, even when the batteries are not actively cycled. This degradation affects the performance, reliability, and economic viability of BESS installations.

Key factors influencing calendar aging include:

• Temperature: Elevated temperatures accelerate chemical reactions within the battery, leading to faster degradation.
• State of Charge (SoC): Storing batteries at high SoC levels (e.g., above 80%) can increase the rate of capacity loss.
• Time: Prolonged storage, even under optimal conditions, contributes to gradual degradation.

These factors lead to the growth of the Solid Electrolyte Interphase (SEI) layer on the anode, consuming active lithium and increasing internal resistance, thereby reducing the battery’s capacity and efficiency.

Impact on Battery Energy Storage Systems (BESS)

1. Capacity Reduction: Calendar aging diminishes the energy storage capacity of BESS, limiting the amount of energy available for dispatch and reducing the system’s effectiveness in applications like peak shaving or load balancing.
2. Increased Internal Resistance: As internal resistance rises, the efficiency of energy conversion decreases, leading to higher energy losses during charging and discharging processes.
3. Economic Implications: Decreased capacity and efficiency can shorten the service life of BESS, impacting return on investment and increasing the levelized cost of storage.
4. Operational Challenges: To mitigate the effects of calendar aging, BESS operators may need to implement more sophisticated energy management strategies, potentially increasing operational complexity and costs.

Mitigation Strategies

To minimize the impact of calendar aging on BESS:

• Temperature Control: Maintain optimal operating temperatures (typically around 25°C) to slow down degradation processes.
• SoC Management: Avoid storing batteries at high SoC levels for extended periods; instead, maintain a moderate SoC (e.g., 40-60%) during idle times.
• Regular Cycling: Periodic charging and discharging can help prevent the buildup of detrimental chemical layers within the battery.
• Advanced Battery Management Systems (BMS): Utilize BMS with algorithms designed to optimize charging patterns and thermal conditions, thereby extending battery life.

Understanding and addressing calendar aging is crucial for the sustainable operation of BESS. By implementing appropriate mitigation strategies, operators can enhance system longevity and performance.