With the continuous growth of new energy demand and the transformation of energy structure, the market scale of energy storage technology continues to expand. As an important part of the battery module in the energy storage system, the energy storage PCB plays a key role in the safety and performance of the entire system. Today we will talk about the characteristics of energy storage PCB.
What is energy storage: Energy storage refers to the storage of energy, which refers to the process of storing energy through media or equipment and releasing it when needed.
Let's take a look at the upstream and downstream products of the energy storage industry and related industry profiles.
It can be seen that the upstream industry is mainly based on materials and related system equipment, while the midstream industry is mainly based on energy storage installation systems and integrated systems. After reaching the midstream industry, you will find that it is closer to our PCB industry. In addition, there are various downstream application-level products, such as photovoltaic products, charging pile products, etc.
Take the familiar lithium battery and photovoltaic as an example, because various control systems, such as battery management system BMS, photovoltaic inverter, and lithium battery charging pile products, all need to be implemented with PCB boards.
So what do PCB products in the energy storage industry look like? The editor deliberately found a few storage boards on the Internet to show you, and they look like this.
Copper substrate for energy storage power supply
Energy storage inverter board
Portable 12v energy storage pcb board
From the picture above, what are the characteristics of the energy storage pcb board?
1. It is difficult to find BGA chips and some fine-pitch devices on energy storage PCB boards, mainly for charging and discharging;
2. The energy storage board generally has thicker copper, most of which are above 2oz; and it is mainly used for high current, accompanied by high voltage (up to kilovolts).
3. It is also because the board is more prone to heating problems due to the operation of high current, so the energy storage PCB board will be treated for heat dissipation, such as drilling heat dissipation holes or adding some heat dissipation shells.
So what should be paid attention to in the design and manufacture of energy storage PCB?
First, due to the existence of high current, the power ground will be disturbed when it flows through a large current; secondly, EMC interference radiation is easily generated during the change of high current.
Therefore, we should pay attention to the following points when designing and manufacturing energy storage PCBs:
1. Choose high-performance materials suitable for high-current applications as much as possible, such as FR-4, metal substrates, and composite materials. These materials have low resistance, high thermal conductivity and good mechanical strength, and can withstand large currents under heat and current concentration effects.
2. The current distribution is balanced. Reasonable current distribution can reduce the resistance and hot spots of the current path. For example, adding a balance current device, balance resistance or current balance layer can improve the reliability and stability of the circuit board.
3. When wiring on the PCB, try not to cross the high current path and the digital signal to avoid mutual interference.
4. The high current path should be treated with solid copper as much as possible. First, the current carrying capacity is relatively large;
5. The heat generated by high current will damage the device and the product, so the power path should be paid more attention to. Generally, a large area of copper is laid, holes are drilled, and the external resistance soldering layer is dug out to expose the copper skin to speed up heat dissipation.
6. The EMC radiation problem of large currents should be considered during the layout, and methods such as thickening the line width, increasing the aperture, and increasing the spacing design can be adopted. Keep the high current path as short as possible, and place it away from easily interfered devices (signal interference and thermal influence) when planning the path.
What are the difficulties in the manufacture of energy storage pcb boards?
Because of the influence of high current, thick copper plates are generally required, and thick copper plates will have processing difficulties such as the following during the manufacturing process.
1. Difficulties in etching
Because of the increase of copper thickness, it is more difficult to exchange the potion. In order to reduce the amount of side erosion caused by the exchange of potion as much as possible, multiple rapid etching is required. With the increase of the amount of side erosion, it is also necessary to increase the etching compensation coefficient. way to compensate for side erosion.
2. Difficulties in lamination
With the increase of copper thickness, the line gap is deeper, and the required resin filling amount needs to be increased accordingly; since it is necessary to use resin to fill the line gap and other parts to the maximum, the prepreg with high glue content and good resin fluidity is the thickest First choice for copper plates. However, the increase in the use of prepreg will also increase the risk of sliding boards. It is common to use the method of adding rivets to strengthen the degree of fixation between the core boards.
3. Difficulties in drilling
Thick copper plates are usually thicker than 2.0mm. When drilling, the energy of X-RAY gradually decays with the increase of copper thickness, and its penetration ability will reach the upper limit. There will also be a problem of cracking the pad when drilling the PCB. The traditional improvement method is to increase the pad, increase the peeling strength of the material, and reduce the cutting speed of the drilling hole.
Anyway, Huaqiu has been deeply involved in the PCB industry for many years. We already have rich experience in the production of energy storage PCB boards. Huaqiu has also been working hard to improve the process capability, which can meet the various needs of customers for products. Fans can rest assured Come over here. Huaqiu has been committed to providing customers with high-reliability multi-layer board manufacturing services, focusing on PCB R&D and manufacturing, with its own environmental protection qualifications, providing customers with high-reliability and short-term delivery board experience. It is a global customer of 300,000+ The preferred PCB intelligent manufacturing platform.
At the same time, Huaqiu's electronics supply chain business covers the three core links of PCB circuit boards, electronic components, and the final PCBA in the electronics industry. It has fully opened up the upper, middle and lower reaches of the electronics industry, forming a one-stop electronics industry chain service platform, and accelerate the construction of a closed-loop ecology of the electronics industry.
In the future, Huaqiu will, as always, adhere to the user-centered approach, strive for excellence from quality to service, and continue to provide customers with high-quality, short delivery, and cost-effective one-stop services.