Prismatic Lithium Batteries

Drone Battery

ENOV High-Energy drone batteries power industrial and commercial drones. Delivering 220–320 Wh/kg energy density, they enable long flight times (30+ mins) and support fast charging (2C). Perfect for aerial photography, surveillance, and delivery drones.

I. Basic Definition and Core Structure of Prismatic Lithium-Ion Batteries

(I) Definition Scope

Prismatic lithium batteries are one of the important packaging types of lithium-ion batteries. They have a rectangular or square shape and, together with cylindrical lithium-ion batteries (such as models 18650 and 21700) and pouch lithium-ion batteries, constitute the mainstream categories of lithium-ion batteries. The electrode materials are mostly arranged in layers and encapsulated in a sturdy metal casing. Owing to their unique flat design, they have significant advantages in space utilization and are widely used in equipment with strict requirements on installation space.

(II) Composition of Core Structure

• Casing: The mainstream materials used are aluminum alloy or stainless steel. Domestic power battery manufacturers prefer aluminum casing design. Aluminum casing not only has a simple structure but also can effectively reduce the weight of accessories. Compared with cylindrical batteries, it further improves energy density while providing reliable physical protection for the internal components of the battery to resist external impact and extrusion.

• Cell: It is composed of four core components: positive electrode, negative electrode, separator, and electrolyte. The electrode assembly processes are divided into lamination and winding. The two processes have their own characteristics: the lamination process is superior in terms of energy density and consistency, while the winding process is more suitable for large-scale mass production. The appropriate process can be selected according to different application requirements.

• Safety Devices: They are equipped with explosion-proof valves as standard (the butterfly-type design has the best performance). Some high-end models are also equipped with pressure relief valves and composite current collectors, and integrate PTC (Positive Temperature Coefficient thermistor) and CID (Current Interrupt Device). These devices form a multi-layer safety protection system that can quickly respond when the battery is overcharged, over-discharged, short-circuited, or experiencing abnormal temperature, thereby reducing the risk of thermal runaway. For example, the temperature of some new models in the needle penetration test is only 45°C, which is much lower than the over 100°C of traditional solutions.

II. Performance Characteristics, Advantages and Disadvantages of Prismatic Lithium-Ion Batteries

(I) Core Performance Advantages

• High Energy Density: The compact structural design enables the battery to utilize its internal space fully, allowing it to store more electrical energy within the same volume. The theoretical energy density is higher than that of cylindrical batteries. In 2025, the energy density of mainstream prismatic lithium iron phosphate batteries will continue to increase. When combined with CTP (Cell to Pack) technology, they can better meet the long-range needs of electric vehicles. The range of some models equipped with prismatic batteries has exceeded 1,000 km.

• Excellent Space Utilization: The square design enables a tight arrangement, which can flexibly adapt to the installation space of different equipment. Especially in the battery packs of electric vehicles and energy storage systems, it can maximize the filling of space, reduce idle areas, and improve the energy storage efficiency of the entire system.

• Flexible Customization: The dimensions can be adjusted according to the specific needs of the product it is equipped with. Parameters such as thickness, length, and width can all be customized. The common VDA standard (e.g., 148×26×91mm) is a typical example. This flexibility has enabled its rapid popularization in the early electric vehicle field. Car manufacturers can customize the battery size according to the vehicle design without being limited by the fixed standards of cylindrical batteries.

• Long Cycle Life: Taking prismatic lithium iron phosphate batteries as an example, their cycle life can reach more than 2,000 times. They can withstand multiple charge-discharge cycles while maintaining stable performance. They have significant advantages in scenarios that require long-term and reliable operation, such as energy storage systems, and can reduce the later maintenance and replacement costs of equipment.

• High Charge-Discharge Efficiency: They have high charge-discharge efficiency and support fast charging and discharging, which can meet the user’s demand for fast response of equipment. For example, in the field of electric vehicles, when combined with fast charging technology, the charging time can be greatly shortened, improving the convenience of use.

• Stable Voltage Platform: They use the same positive and negative electrode materials and electrolyte as cylindrical and lithium-polymer batteries, so their theoretical discharge platform is the same. Moreover, due to their slight advantage in internal resistance, the actual discharge platform is slightly higher, which can provide continuous and stable power output for equipment and ensure the stability of equipment operation.

(II) Main Performance Shortcomings

• Difficult Heat Dissipation: Although the metal casing can provide protection, it also affects the heat dissipation efficiency. Especially when used in groups, a special heat dissipation system (such as liquid cooling assistance) must be designed; otherwise, local overheating is prone to occur, which affects the battery performance and service life.

• Low Standardization Level: The customization feature leads to the existence of thousands of size models in the market. It is difficult to unify the production process, and the consistency of individual units is poor during automated production, which may affect the overall performance and service life of the battery pack and increase the difficulty of industrial chain.

• Relatively High Weight: Due to the use of a metal casing, compared with the aluminum-plastic film packaging of pouch batteries, their weight is higher. In scenarios with extremely high requirements for equipment lightweight (such as some portable electronic devices), their competitiveness is slightly inferior to that of pouch batteries.

• Risk of Tab Welding: The difficulty of tab welding is higher than that of cylindrical batteries, and cold soldering is prone to occur. Cold soldering will affect the stability of the electrical connection of the battery, thereby reducing the battery quality and increasing the risk of failure, which has high requirements for the precision of the production process.

• Performance Attenuation at Corners: The chemical activity at the corners of the battery is relatively poor. After long-term use, the performance of the corner areas degrades more significantly, which may lead to an accelerated rate of overall capacity attenuation of the battery and shorten the battery service life.

III. Comparison Between Prismatic Lithium-Ion Batteries and Other Types of Lithium-Ion Batteries

Comparison Dimension	Prismatic Lithium-Ion Batteries	Cylindrical Lithium-Ion Batteries (e.g., Model 4680)	Pouch Lithium-Ion Batteries
Space Utilization	High (tight arrangement, suitable for limited space)	Low (more gaps between cells, more space waste)	Extremely high (customizable shape, suitable for complex installation space)
Grouping Efficiency	85%-90% (supports CTP technology, reducing the module link)	70%-75% (small single-cell capacity, requiring more cell combinations)	Over 90% (flexible structure, large space for grouping design)
Heat Dissipation Performance	Medium (requires liquid cooling assistance for heat dissipation to avoid local overheating)	Excellent (large surface area, good air circulation, good natural heat dissipation effect)	Poor (relies on external packaging for heat dissipation, high difficulty in thermal management)
Production Cost	Approximately 0.5 CNY/Wh in 2025 (lithium iron phosphate system, yield rate reaches 98%)	15% lower (high standardization level, significant benefits from large-scale production)	High (aluminum-plastic film relies on imports, high complexity of production process)
Consistency	Depends on process (lamination process can improve consistency, but still needs optimization)	Optimal (mature automated production, long-term technical accumulation ensures consistency)	Poor (swelling is prone to occur during packaging, affecting the consistency of individual units)
Mechanical Strength	Strong (metal casing has excellent impact and extrusion resistance)	Relatively strong (steel casing protection, good mechanical stability)	Weak (aluminum-plastic film material is fragile, requiring additional protective structure)
Application Scenarios	Electric vehicles, energy storage systems, some consumer electronics	Electric vehicles, power tools, energy storage systems	Portable consumer electronics such as mobile phones and tablet computers

IV. Application Fields of Prismatic Lithium-Ion Batteries

(I) Electric Vehicle Field

Mainstream domestic new energy vehicle manufacturers such as NIO, Geely, SAIC, and GAC all use prismatic lithium-ion batteries. Star products such as BYD’s “Blade Battery” and CATL’s Kirin Battery are all developed based on prismatic battery technology, which can meet the demand for large capacity and high energy density of electric vehicles and provide the vehicles with a range of more than 1,000 km. Up to now, the market share of prismatic batteries in the domestic power battery market has exceeded 90%. At the same time, it has attracted international manufacturers such as South Korea’s SK On and LG Energy Solution to adjust their strategies and set up special teams to develop prismatic batteries, further expanding its influence in the global electric vehicle battery market.

(II) Energy Storage System Field

In the energy storage field, prismatic lithium-ion batteries are widely used in household energy storage, grid-level energy storage, solar energy storage systems, and backup power systems due to their long cycle life, stable performance, and high grouping efficiency. In the domestic energy storage project bidding in the second quarter of 2025, prismatic lithium iron phosphate batteries accounted for 85%. Their large single-cell capacity can reduce the number of parallel cells, lower the complexity of the Battery Management System (BMS), improve the reliability and operating efficiency of the energy storage system, and reduce the overall operating cost.

(III) Consumer Electronics and Industrial Equipment Field

In the consumer electronics field, prismatic lithium-ion batteries are suitable for some drones, power tools, and portable devices. They can be flexibly customized according to the device size to meet the dual needs of the device for space and energy. In the industrial equipment field, equipment with high requirements for battery stability and safety, such as medical instruments and backup power supplies for communication base stations, also often use prismatic lithium-ion batteries. Their reliable performance can ensure the continuous and stable operation of industrial equipment and reduce the risk of failures caused by power supply problems.