I. Background of Large-scale Energy Storage Systems for Wind, Solar and Electric Energy

Energy transition and the demand for sustainable development
▲ Global goal-driven: Against the backdrop of the global "carbon neutrality" goal, traditional fossil energy is gradually being replaced by renewable energy due to its high carbon emissions. The International Energy Agency predicts that by 2050, renewable energy sources such as wind and solar power will account for more than 80% of the global electricity supply.
▲ Strong policy support: The EU's "European Green Deal" aims to achieve climate neutrality by 2050, and China's "14th Five-Year Plan" also highlights wind power and photovoltaic power as key areas for energy structure adjustment.

The inherent characteristics of wind energy and solar energy
▲ Intermittency and instability: The generation of wind and solar energy is greatly influenced by natural conditions. Wind energy is affected by changes in wind speed and direction, while solar energy is influenced by the alternation of day and night, seasonal changes, weather conditions, etc. It is intermittent and unstable, making it difficult to provide continuous and stable power supply.
▲ Mismatch between energy supply and demand: During peak energy demand periods, there may be insufficient wind and solar power generation. During off-peak hours, there may be an excess of power generation, leading to an imbalance between energy supply and demand.

Driven by market and economic factors
▲ Continuous cost decline: With the continuous maturation and large-scale application of wind and solar power generation technologies and energy storage technologies, their costs are gradually decreasing, making projects that combine wind, solar and energy storage more economically feasible.
▲ New energy lithium batteries, with their advantages of high energy density, long cycle life and environmental friendliness, have gradually become the preferred solution for wind energy, solar energy and electric energy storage systems. This solution is designed to meet the application requirements of lithium batteries in wind energy, solar energy and electric energy storage system equipment projects, ensuring that lithium batteries can provide safe, efficient and customized power supply solutions for their equipment in special fields.

II. Analysis of Equipment Demand Characteristics
1. Equipment application characteristics
▲ Equipment type: Used for power storage in wind power plants, photovoltaic power plants, etc.
▲ Working environment: Temperature range, from -40℃ to +70℃, high temperature, extremely cold, high humidity environment, etc.
▲ Power demand: Large continuous/peak power, long battery life. The voltage platform generally adopts 12.8V or 48V and other voltage platforms.

2. Core requirements for lithium batteries
High security: Mature and standardized technology, with minimal environmental impact, etc.
▲ Long cycle life: ≥2000 times (80% capacity retention rate).
▲ Fast charging: Supports fast charging and is suitable for high-intensity work.
▲ High-power discharge: The battery supports continuous high-current discharge, meeting the high-current requirements of high-power devices and ensuring their continuous and stable operation.
▲ Intelligent management: The BMS (Battery Management System) is equipped with functions such as overcharge protection, overdischarge protection, overcurrent protection, short-circuit protection, temperature protection, and fault diagnosis, making the battery more intelligent.
▲ Discharge temperature range: -40℃ to +70℃. In a low-temperature environment of -40℃, the battery's discharge efficiency is over 70%. A wider range of ambient temperature adaptability.
▲ Charging temperature: -20 ℃ to +50℃ range, with a wider adaptability to environmental temperatures.

III. Scheme Design
1. Battery selection
▲ Cell types: Ternary lithium batteries (ultra-low temperature, high energy density, high safety), lithium iron phosphate batteries (ultra-low temperature, high safety, long life), sodium-ion batteries (high safety, long life, good low-temperature performance). Different system cells are selected and matched according to different application scenarios.
▲ Battery combination configuration structure: Series and parallel schemes are designed based on the required voltage and capacity of the equipment to meet the requirements of different output voltage platforms.
▲ Structural design: IP65 to IP68 protection grade, shock-resistant structure, explosion-proof enclosure (suitable for extreme environments or flammable and explosive environments).

2. BMS Management System
Core functions:
▲ Real-time monitoring of the voltage, temperature, SOC (State of Charge), and SOH (State of Health) of individual battery cells.
▲ The battery charging active balancing technology enhances the consistency of usage among battery cells and extends the lifespan of the battery pack.
▲ The I2C/SMBUS/CAN/RS485 communication interface enables data interaction and communication with the main control system of the equipment.
▲ The Coulomb computing method makes the battery SOC more accurate and the battery smarter.

3. Charging solution
▲ Charging equipment: Customized intelligent solar photovoltaic and wind energy conversion, supporting constant current and constant voltage (CC-CV) charging.
▲ Charging strategy: Select fast charging or slow charging mode based on the working conditions to prevent battery overload.
▲ Intelligent control and management: Based on the technical performance characteristics of the battery, the battery charging process and fault diagnosis are intelligently controlled.

IV. Safety and Compliance
1. Safety protection
▲ Thermal management: By adopting a reasonable structural layout, thermal runaway is reduced. Air cooling/liquid cooling systems can be used (for high-power scenarios) to ensure temperature uniformity during battery use and effectively control battery thermal runaway.
▲ Fault protection: Multiple hardware protection mechanisms such as overcharge, overdischarge, short circuit, overcurrent, and over-temperature.
▲ Fault protection: Multiple hardware protection mechanisms such as short circuit, overcurrent, and over-temperature.
▲ Explosion-proof certification: The design can pass various safety regulations certifications.

2. Standard compliance
▲ It complies with national standards such as GB31241-2022 (Safety Technical Specification for Lithium-ion Batteries and Battery Packs for Portable Electronic Products), GB 17761-2024 (Safety Technical Specification for Electric Bicycles), GB/T 34131 (Lithium Batteries for Power Storage), GB 38031 (Safety Requirements for Batteries for Electric Vehicles), etc.
▲ How to obtain domestic and international certifications: GB certification, UN38.3 certification, UL certification, IEC certification, CE certification and other various certification requirements;

V. Project Implementation Plan

VI. Economic Benefit Analysis
1.In terms of cost
▲ The initial investment in the early development stage is relatively large, which gives it an absolute advantage in terms of long-term usage costs.
2. Energy-saving benefits:
▲ It can increase the self-sufficiency rate of energy, balance peak and valley loads, optimize electricity charges, and reduce the pressure on the power grid.
3. Maintenance cost:
▲ The long service life of equipment leads to cost dilution, and intelligent operation and maintenance reduces labor costs.

VII. After-sales Service
1. Warranty period: 5 to 10 years of after-sales warranty, with a lifespan of over 3,000 to 5,000 cycles (whichever comes first).
2. Remote monitoring: According to the actual demand status, the cloud platform provides real-time monitoring of the battery status and early warning of potential faults.
3. Emergency Response: Respond within 4 hours, provide solutions within 8 hours, and offer on-site technical support within 24 to 48 hours.

Hint:
▲ The plan needs to be refined based on specific equipment parameters (such as voltage, capacity, and size limitations).
▲ If special environments are involved, corresponding protective designs need to be added.
▲ It is recommended to conduct joint debugging with the equipment manufacturer to ensure that the battery is compatible with the entire machine system