Design Scheme of Lithium Battery for Electric Forklift
In the early days, lead-acid batteries were used in electric forklifts, but lead-acid batteries were large in size and low in energy. The new lithium battery is higher than energy, the same power/capacity is small, the weight is light, and the cycle life is long. Nowadays, the logistics forklifts generally use lithium batteries instead of lead-acid batteries. Division I combined with the characteristics of the industry and customer demand, choose lithium iron phosphate battery scheme supporting customers electric forklift products, batteries can continue to work with high current, the protective plate used imported IC and MOS tube control management, the service life of lead-acid batteries 3-5 times.
Design requirements for lithium batteries for electric forklifts:
The battery design is applied to the use of logistics forklifts. It requires a small size and a long working time. It can drive two motors: one is the drive vehicle operation and the other is the drive object. Our Li-iron phosphate battery electric forklift scheme is designed with a total power of 800W and an instantaneous power of 1000W. The appearance is damp-proof, the cycle life is long, and the performance of high power and high current discharge is good. The whole product adapts to the indoor environment, the temperature rise should be low.
Design scheme of lithium battery for electric forklift:
1) Protection plate(PCM): According to the chemical characteristics of lithium iron phosphate batteries and the working characteristics of forklifts, targeted design protection lines, in addition to overcharge, overdischarge, Overflow, short-circuit protection and other functions, The protection plate design also fully considers the problem of high-power heat dissipation and the balance of the entire battery. The entire protection plate uses aluminum alloy as the heat dissipation substrate, and the temperature rise is less than 20 degrees.
2) Protection circuit: Adopt imported IC and MOS tubes to carry out online real-time monitoring of the functions of overcharge, overdischarge, Overflow, short-circuit, etc., so that the core works within a safe, stable, and efficient range.
3) Overcurrent fuse: mainly for the lithium battery battery itself battery management system protection failure design. Since the battery pack uses a high-power core with a relatively large capacity, although the battery management system has overcurrent and short-circuit protection, if there is an anomaly, the protection function will fail, and a very large current will be generated in the case of an output short circuit, resulting in danger. occur, Therefore, an overcurrent fuse is added to the scheme. When an abnormal short circuit occurs, the fuse breaks off the loop and can not be restored to achieve the purpose of abnormal protection.
4) Core: The LARGE26650/3 .2 V/3000 mAh phosphate lithium core is used. The maximum charge capacity of the core can reach 1C, and the maximum discharge rate can reach 2C. The core itself has multiple safety protection functions. The core has a built-in thermistor(PTC), and the unit structure is also isolated by PTC when combined to prevent the phenomenon of surge flow.
5) Whole group battery parameters: 25.6 V/80Ah(usually labeled: 24 V80Ah). Normal operating current 30A, maximum operating current up to 50A, instantaneous start current up to 120A.
6) Resistance balance is used in the interior of the battery, which can effectively compensate for the reduction in capacity caused by the difference in single core during use, and maximize the service life of the battery. 7) Battery parallel unit: PTC isolation is used to avoid the safety problems caused by large capacity.
8) The large current main circuit of the battery uses a copper belt as a collector, so that the discharge current of the single battery is as close as possible.
9) The battery pack uses a plastic bracket to isolate and fix the core, which is more conducive to the heat dissipation and safe use of the battery.