With the increasing popularity of electric vehicles (EVs), the need for reliable and efficient batteries has become paramount. Two of the most commonly used lithium-ion batteries in EVs are lithium iron phosphate (LiFePO4) batteries and ternary lithium batteries. Each type has its own set of characteristics, advantages, and disadvantages. However, in recent years, a new type of battery called “blade battery” has emerged as a potential game-changer in the EV industry. In this blog post, we will explore the differences between LiFePO4 batteries, ternary lithium batteries, and blade batteries. We will also discuss the advantages and disadvantages of blade batteries in detail.
Quick Read
Ternary lithium batteries have lower cost and longer cycle life, but poor thermal stability.
Car companies use ternary lithium batteries for their high energy density, while lithium iron phosphate batteries are preferred for their thermal stability.
Blade batteries have better safety, volume utilization, cycle life, and structural strength compared to ordinary lithium iron phosphate and ternary batteries.
Blade battery cells are arranged vertically in a battery pack, simplifying the structure and improving space utilization.
Understanding LiFePO4 Batteries versus Ternary Lithium Batteries
Lithium iron phosphate (LiFePO4) batteries are known for their lower cost, long cycle life, and excellent thermal stability. These qualities make them a popular choice for commercial vehicles such as electric buses. On the other hand, ternary lithium batteries are preferred by most car companies due to their higher energy density and better low-temperature performance. Although they offer longer ranges compared to LiFePO4 batteries under the same weight, they have poor thermal stability, high production technology thresholds, and higher raw material costs.
Blade Batteries
Blade battery is essentially a variant of LiFePO4 battery technology developed by BYD in 2020. It adopts high-safety lithium iron phosphate technology with improved volume and energy density. The unique feature of blade batteries is their flexible structure that can be customized according to available space within an electric vehicle.
Advantages of Blade Batteries
Flexible Structure:
One major advantage of blade batteries is their flexible structure that allows customizing the length of each battery, maximizing space utilization within the vehicle. Compared to traditional lithium iron phosphate batteries, blade batteries offer a 50% increase in volume utilization rate, rivaling that of ternary lithium batteries.
High Strength:
Blade batteries are designed in a way that enhances their structural strength. By tightly arranging hundreds of blade battery cells with a length of less than one meter together, they provide additional support to the safety structure of the vehicle during collisions. This design improves overall vehicle safety.
Longer Battery Life:
Blade batteries inherit the long cycle life of lithium iron phosphate technology. With LiFePO4 as its core, blade batteries can endure thousands of charge and discharge cycles, ensuring a longer lifespan compared to other battery types on the market.
Excellent Safety Performance:
Blade batteries have undergone rigorous testing for safety. In puncture tests, the surface temperature only reaches 30-60 degrees Celsius, reducing the risk of spontaneous ignition and enhancing overall safety during use.
Disadvantages of Blade Batteries
Poor Low-Temperature Performance:
Like other lithium iron phosphate batteries, blade batteries exhibit reduced performance in cold winter conditions. The power output may be significantly lower due to limitations associated with this chemistry. This is an inherent characteristic that needs to be considered in regions with extremely low temperatures.
Higher Maintenance Cost:
Due to their unique structure where each battery cell acts as its own bracket without additional support structures, blade batteries require higher maintenance costs. If one battery cell is damaged or needs replacement, it may affect other cells within the series connection.
Higher Manufacturing Cost and Process Difficulty:
The manufacturing cost and process difficulty for blade batteries are higher compared to traditional battery technologies. The laminated process used in manufacturing allows for better energy density and improved safety but adds complexity and cost to production.
Technological Innovations in Blade Batteries
To address some of the limitations associated with lithium iron phosphate batteries, blade batteries incorporate two groundbreaking technologies:
Large-Size Laminating Process:
Blade batteries utilize a large-size laminating process instead of the traditional winding structure. This results in a more uniform current density and better internal heat dissipation, enabling high-power charging and discharging. The laminated structure also improves cycle characteristics and safety features.
Comprehensive High-Temperature Ceramic Battery Technology:
To enhance performance and safety factors, ceramic coatings are applied to blade batteries. These coatings prevent severe reactions during short periods within the battery cell, significantly improving safety and cycle life. High-temperature ceramic coatings are used in key parts to insulate against high temperatures.
Understanding Blade Battery Lifespan
It is important to note that the manufacturer does not state that the service life of a blade battery is limited to “only 8 years.” Instead, they claim that the service life can reach up to 8 years. The theoretical data provided by the manufacturer indicates that a blade battery can last for 1.2 million kilometers within 8 years, supporting more than 3,000 charge and discharge cycles. It is crucial to understand that battery lifespan gradually decreases over time, rather than having an abrupt expiration date like food products.
Summary
The lithium-ion batteries used in electric vehicles are mainly equipped with lithium iron phosphate batteries and ternary lithium batteries.
Ternary lithium batteries have lower cost and longer cycle life compared to lithium iron phosphate batteries, but they have poor thermal stability and high production technology threshold.
Car companies currently use ternary lithium batteries mainly for their high energy density, while lithium iron phosphate batteries are preferred for their thermal stability.
Blade batteries are essentially lithium iron phosphate batteries with a long thin structure design and high-safety features. They have better safety, volume utilization, cycle life, and structural strength compared to ordinary lithium iron phosphate and ternary batteries.
Blade battery cells are arranged vertically in a battery pack, which simplifies the structure and improves space utilization. The blade battery has a flexible structure that allows for customization of the length to make full use of the car’s space.
In conclusion, blade batteries offer several advantages over traditional lithium iron phosphate and ternary lithium batteries in terms of flexible structure, strength, longer battery life, and excellent safety performance. However, they do have some disadvantages such as reduced low-temperature performance, higher maintenance costs, and increased manufacturing complexity. Technological innovations in large-size laminating processes and high-temperature ceramic coating make blade batteries an intriguing option for EV manufacturers looking for improved energy density without compromising safety or cycle life.
By continually pushing technological boundaries and addressing limitations associated with lithium-ion battery chemistries, blade batteries represent an exciting development in the electric vehicle industry. As advances in battery technology continue, we can expect to see further improvements in energy density, performance, and safety of electric vehicle batteries.
Frequently Asked Questions
What are the advantages of BYD's Blade Battery Technology over traditional battery technologies?
BYD's Blade Battery Technology offers several advantages over traditional battery technologies. It has a higher energy density, providing longer driving ranges for electric vehicles. The design reduces the risk of thermal runaway, improving safety. The compact size allows for better space utilization in EVs. Additionally, the Blade Battery has a longer lifespan, reducing the need for frequent replacements.