What is an energy storage battery PACK?
An energy storage battery pack is not just a single "battery," but rather an integrated energy storage and management unit. Its core function is to combine numerous individual cells through a scientific series-parallel arrangement, then integrate them with a battery management system (BMS), thermal management system, electrical components, and protective enclosure to form a complete energy package ready for immediate use in energy storage scenarios.
The value of the pack lies in its integration of various components, which addresses the limited capacity of individual cells. Not only does it provide higher voltage and capacity, but the BMS and thermal management system also ensure the safety, efficiency, and longevity of the entire unit during charging and discharging, making it an indispensable core power source in energy storage systems.
The five core components of PACK are indispensable
A battery pack can be specifically divided into five core modules.
The battery module is the "energy heart" of the pack. It's a "small unit" composed of multiple single cells connected in series and parallel. For example, connecting 12 3.2V cells in series creates a 38.4V module. Connecting multiple such modules in parallel further increases capacity. Its core function is to "store and release electrical energy." Different module types can be selected based on the voltage and capacity requirements of the energy storage scenario.
The electrical system is the "blood vessels and nerves" of the pack. As the energy transmission and signal transmission network, it primarily consists of connecting copper busbars, high-voltage wiring harnesses, low-voltage wiring harnesses, and electrical protection devices (such as fuses and relays). The high-voltage wiring harness is responsible for transmitting the high-voltage electrical energy stored in the battery module to external loads (such as inverters), serving as the core channel for energy transfer. The low-voltage wiring harness transmits BMS control signals and battery cell status signals (such as voltage and temperature) to various components in real time, ensuring the coordinated operation of the entire system. The connecting copper busbars serve as the "conductive bridge" between battery cells and modules, requiring low resistance and strong conductivity to avoid potential overheating caused by poor contact.
The thermal management system is the "smart air conditioning" of the pack. Batteries are most vulnerable to uneven heating and cooling. Excessive temperatures can cause cell bulging, shorten battery life, and even pose safety risks. Excessive low temperatures significantly reduce charging and discharging efficiency. Therefore, the thermal management system creates a "constant temperature environment" for the pack, ensuring that all battery cells operate within a temperature range of 5°C or less. The current mainstream thermal management methods are divided into two categories. Air cooling uses fans, heat exchangers and other components to remove heat through air flow. It has a simple structure and low cost, and is suitable for small and medium-power energy storage scenarios (such as household energy storage). The core components include compressors, fans, heat exchangers, etc., and have high assembly flexibility. Liquid cooling absorbs heat through the circulation of coolant, has higher temperature control accuracy and stronger heat dissipation efficiency, and is suitable for high-power energy storage power stations (such as photovoltaic supporting energy storage).
The box is the "skeleton and armor" of the PACK. As an external protective structure, it is mainly composed of the box body, cover, metal bracket, and fixing screws. It has three core functions: the support function is to fix the internal battery modules and electrical components to ensure structural stability; the protection function is to resist external mechanical impact (such as collision) and vibration, while preventing dust and moisture from entering the interior, meeting the protection requirements of outdoor energy storage scenarios (usually requiring an IP65 protection level); some boxes also integrate fireproof materials to further enhance safety performance.
The BMS is the "brain and center" of the battery pack. As the intelligent control core, it is responsible for real-time monitoring and precise management of the entire battery system. Its main functions include condition monitoring, charge and discharge management, balancing control, and data transmission. Condition monitoring collects the voltage, current, and temperature of the battery cells, as well as the state of charge (SOC) and state of health (SOH) of the entire pack in real time. Charge and discharge management prevents overcharge, overdischarge, and overcurrent, ensuring that the charge and discharge process remains within a safe range. Balancing control adjusts the cell state through active or passive balancing when voltage differences occur between cells, preventing life degradation due to poor consistency. Data transmission uploads monitored data to the MES or energy storage system control platform for remote monitoring and operation and maintenance.
