Preface: In the field of electric forklift, previously due to the consideration of cost and safety factors, lead-acid battery is still dominant, lithium forklift accounted for less than 30%, but in recent years, with the application cost of lithium battery declining year by year and the safety of greatly increased, the replacement of lithium electric power to lead-acid battery power is greatly accelerated.
Since last year, CeramiX team has received the design and production of lithium battery powered packs for forklifts and accumulated certain experience.
At the same time, we also found that in the forklift lithium battery market there are a variety of good and bad phenomenon, which is prominent is the quality and price is relatively chaotic. Therefore, in view of this phenomenon, we make a simple analysis of the current cost of lithium battery for forklift based on our experience in this field and feedback from market survey, hoping that it will be helpful to customers who have this demand.
1.Composition of lithium battery products
Generally speaking, a complete power lithium battery system is usually composed of cell, battery management system (BMS), functional components, wiring harnesses, structural parts and other related components. Power lithium battery system mode can be divided into three different levels of mode, namely cell mode, BMS mode, Pack system integration mode.
2. lithium battery cell cost
Battery cell: The battery cell is the most basic unit and the most important part of the lithium battery pack. The battery cell is generally not used directly, and requires BMS or simple protection board. The quality of the battery cell directly determines the quality of the battery pack. There are currently fewer than 100 lithium cell factories in China, with a wide range of quality ranging from simple lithium batteries for flashlights to batteries for the automotive industry. Generally speaking, the cell produced by new equipment and new technology has good quality, high energy density, stable quality and high safety.
The battery cell occupies 80% of the cost of the lithium battery pack, and is the most expensive part of the lithium battery pack, which directly determines the safe life and price of the lithium battery pack. At present, if the cell price in the market is referred to the consistent and qualified cell monomer price of the automobile industry, take lithium iron phosphate battery as an example, the price is generally $0.18~$0.22/WH.
For cell manufacturers, it is impossible for a single cell in mass production to achieve 100% consistency, and there will be voltage difference, capacity difference or resistance difference in each cell. After testing and grading, the consistent products are used for the matching of new energy vehicles. The manufacturer’s quality guarantee conditions can be 5 years /4000 cycles / 10,000 hours / 200,000 kilometers. This part of the cell is called A-class cell. After grading, the products that do not meet the standard are referred to as B-class cell in the industry. The B-class cell are mainly sold to industries with low quality requirements, such as Telecom backup power supply and energy storage requiring about 1000-2000 charging cycles or low-speed electric two-wheeler and three-wheeler industries with a life span of about 3 years. The market price of B-class cell is generally $0.12~$0.14/WH.
3.Battery Management System(BMS)
All regular lithium-ion battery pack, must install BMS, BMS generally adopts the integrated design, integrated the battery voltage, temperature detection, protection, SOC estimation (power estimation), balanced management, communication and remote monitoring, and other functions, the purpose is to protect lithium battery in the process of using safety and prolong the service life of the battery pack. There are many manufacturers producing BMS in China, and there are great differences in quality. Take the BMS of 48V forklift battery pack as an example, the price is generally between USD250-450. In addition, a very small number of safety-conscious lithium battery pack suppliers will use less than $100 protective board (which function like the voltage and time potentiometers of a common lead-acid charger) to save costs. BMS account for about 10% of the cost of a finished lithium battery pack. The price difference between high quality BMS and poor products is about USD350.
4.Pack system includes functional components, wiring harnesses, structural components and other related components
Pack system integration is equivalent to forklift assembly, and the level of technology determines the quality and failure rate. In the use of many finished lithium battery packs, the phenomenon of internal welding fracture usually occurs, and even the products of some large Pack factories will have this problem. Therefore, the quality of cell integration and contacts such as joints are the focus of frequent quality problems.
The differences of functional components can be illustrated by examples. Take relays as an example. The manufacturers that pay attention to safety and quality all use Tyco relays. The single cost of two relays is about USD120/PCS, while some cheap relays only cost USD50/PCS. In addition, there is also a large gap in the quality and price of components such as Hall current sensors.
In terms of Pack production process, Strong manufacturers all use large-power laser welding process to ensure the safety and stability of products. However, some small Pack factories use simple copper strip soft connection to reduce the cost, which cannot guarantee the safety and stability of product use. The cost difference of this part is about USD500.
5.Total cost of lithium battery pack system integration
To sum up, taking lithium iron phosphate 48V/400AH(19.2kwh) as an example, the production and procurement cost of A-class cell is about USD4000/SET(close to the price of high-quality VRLA battery), plus high-quality BMS, after taking into account the functional components, wiring harnesses, structural parts and other related components, counterweight blocks included in Pack system, as well as the company’s management costs, R&D and design expenses, reasonable profits and other factors, the market price range is generally USD7,800 /SET, which is about USD0.4/WH after conversion. This is a relatively reasonable price range. For B-class cell or lower quality cell products, the purchasing cost of the battery is about USD2400 /SET(even cheaper than lead-acid battery), the market price of the whole pack is about USD4800/SET. This translates to USD0.25/WH. If it is 80V/500AH, for example, the cost difference of a battery pack is as high as USD5000. The huge price gap provides a good profit margin for some small lithium battery pack factories that do not pay attention to safety, quality and service life.
In the process of communication with many customers, we often hear some different views, some customers think that the car with A-class cell, forklift with B-class cell is a matter of course. In fact, if you really understand the operating conditions of forklifts, you will find that the quality and safety requirements of lithium batteries in the operating conditions of forklifts will not be lower than those in the automobile industry. However, as lithium battery has not been in the forklift industry for a long time, the forklift industry does not yet have its own lithium battery standard, and it is difficult for customers to distinguish between good and bad products. Even if they open the battery pack to check, they cannot distinguish between good and bad quality or even old and new without testing equipment.
6.summarized
The application of new energy in forklift industry has just begun to develop on a large scale, which is in the ascendant and unstoppable. In this good situation, how can our colleagues in the fierce competition in the market to keep a cool head, down-to-earth to study lithium battery products, to understand the lithium battery industry, the correct choice and use of high quality, high safety lithium battery, together care and cultivate our forklift new energy market. At the same time, I also hope that the majority of colleagues can participate in the discussion and exchange of new energy, bring more positive energy for the development of new energy of forklift, so that lithium can better serve industrial vehicles.
