In today’s era of rapid new energy development, energy storage battery packs, as critical equipment for energy storage, directly impact the economic performance of the entire energy storage system. However, many operators face a common frustration: why do energy storage battery packs, which involve significant investment, often have a much shorter actual service life than expected?
The Truth Behind the Degradation of Energy Storage Battery Packs
In any large-scale energy storage power station, you can hear similar complaints from maintenance personnel: “These batteries have only been used for three years, and their capacity has dropped to just 60% of the nominal value.” This is not an isolated case. Behind it lies a frequently overlooked critical factor—inconsistency within the battery pack.
Imagine a battery pack composed of hundreds of cells in series as a tug-of-war team. When the strength of each team member varies, the overall performance is limited by the weakest link. Similarly, tiny differences in voltage, capacity, and internal resistance among the cells in a battery pack are amplified over long-term cycling, eventually leading to a sharp decline in the performance of the entire battery pack.
A photovoltaic energy storage station in Jiangsu once suffered deeply from this issue. The 200kWh lithium battery pack used at the station saw its overall capacity degrade to 58% of its initial value after just two and a half years of operation. Professional testing revealed that 17% of the cells had severely deteriorated, while another 30% still maintained over 85% of their health. This severe inconsistency was the main culprit behind the early “retirement” of the entire battery pack.
The Revolutionary Power of Active Balancing Technology
Faced with this industry-wide challenge, traditional passive balancing technology falls short. Although passive balancing can alleviate cell differences to some extent, its method of discharging through resistors is not only inefficient but also generates additional heat, making it largely ineffective in high-capacity applications like energy storage systems.
The advent of active balancing technology has completely changed this landscape. The brilliance of this technology lies in its ability to act like an intelligent “energy distributor,” monitoring the status of each cell in real time and directly transferring energy from cells with higher voltage to those with lower voltage. The efficiency of this energy transfer typically exceeds 85%, far surpassing the 30%-40% efficiency of passive balancing.
Zhejiang Guheng Energy Technology Co., Ltd. developed the PBM-PW-B-6405 portable battery pack balancing maintenance device, a standout representative of this technology.
This device adopts an advanced inductive active balancing solution with a balancing current of up to 5A, capable of significantly improving battery pack consistency in a short time. In practical applications, this high-efficiency balancing capability delivers impressive results.
Real Cases Demonstrating the Value of the Technology
In a commercial energy storage project in Guangdong, operators personally experienced the transformative power of active balancing technology. The 150kWh lithium battery pack used in the project saw its usable capacity drop to 63% of the rated value after 18 months of operation. After three months of regular maintenance using Guheng Energy’s balancing maintenance device, the usable capacity of the battery pack rebounded to 82%, equivalent to extending its service life by at least two years.
Even more exciting is the economic benefit brought by this maintenance. The project manager calculated: “Based on current electricity prices and battery costs, this balancing maintenance directly saved us approximately 280,000 yuan in battery replacement costs, while the maintenance investment was less than one-tenth of the savings.”
How to Choose the Right Balancing Solution
For energy storage system operators, selecting a suitable balancing device requires considering multiple factors. The first priority is the size of the balancing current, which directly determines balancing efficiency. Generally, a balancing current of 5A is recommended for energy storage systems to meet the demands of high-capacity battery packs.
Portability is another key consideration. Compared to fixed-installation balancing devices, portable balancers offer greater flexibility, making them particularly suitable for operators with multiple energy storage sites. Maintenance personnel can easily carry the device between different sites, significantly improving its utilization rate.
Ease of operation is also an important factor. Modern balancing devices are typically equipped with large touchscreens and intuitive interfaces, supporting detailed data recording and export functions, all of which greatly enhance daily maintenance efficiency.
Guheng Energy: A Leader in Battery Balancing Technology
In the field of battery balancing technology, Zhejiang Guheng Energy Technology Co., Ltd. has become an industry benchmark through years of dedicated research and development. As a national high-tech enterprise, Guheng Energy holds over twenty patents related to battery management, and its products are widely used in power energy storage, communication base stations, new energy vehicles, and other fields.
Guheng Energy’s latest product, the PBM-PW-B-6405 portable battery pack balancing maintenance device, integrates multiple innovative technologies. In addition to its 5A active balancing capability, the device features a 7-inch high-definition touchscreen, supports automatic identification of various battery types, and generates detailed balancing reports to provide data support for maintenance decisions.
Frequently Asked Questions
Q: How often should balancing maintenance be performed?
A: It is recommended to perform active balancing maintenance on energy storage battery packs at least once a month. If significant differences are observed in certain battery units, the frequency should be increased to once a week until the battery pack stabilizes.
Q: Will using a balancer affect the normal charging and discharging of the battery pack?
A: Not at all. Taking Guheng Energy’s balancing device as an example, it consumes minimal energy during operation (typically less than 0.5% of the total battery pack capacity) and automatically performs balancing during charging and discharging intervals, ensuring no impact on normal system operation.
Q: Is balancing technology suitable for second-life power batteries?
A: Particularly suitable. In fact, active balancing technology is an ideal solution for addressing consistency issues in retired power batteries. In a second-life energy storage project in Shandong, the use of Guheng’s balancing device improved the consistency metrics of the battery pack by over 50%, giving these “retired” batteries a new lease on life.
Let Professional Balancing Technology Create Value for You
The lifespan issue of energy storage battery packs is by no means unsolvable. Through scientific balancing maintenance, the service life of battery packs can be extended by over 30%, significantly improving the return on investment of energy storage systems. Guheng Energy is willing to share its technological achievements in battery balancing with industry partners to jointly promote the sustainable development of the energy storage industry.
For more professional knowledge about battery balancing maintenance or tailored solution recommendations for your specific needs, feel free to contact our technical team anytime. We have also prepared a detailed “Energy Storage Battery Pack Maintenance Guide” to help you systematically master practical techniques for extending battery life. Let us work together to inject longer-lasting vitality into every energy storage battery pack.
