1、 From an application perspective:
1. Power lithium batteries can be applied to products with high rate discharge such as electric vehicles, electric vehicles, and power tools, while ordinary 3C lithium batteries are only used for mobile phones, wristbands, digital cameras, laptops, mobile power supplies, and can only meet the needs of ordinary discharge power supply.
2. In product applications, it can be understood that the discharge current of power lithium-ion batteries generally refers to the discharge standard based on 5C current. If it is an ultra-high rate power battery, it can discharge at a current of 10C or 30C or higher; Ordinary 3C lithium batteries are generally judged based on the discharge current below 3C.
2、 From a design perspective:
1. In the development and design of lithium iron phosphate power lithium-ion batteries, more consideration needs to be given to reliability and consistency. After all, it takes a long time (at least 5-10 years), harsh environments (low temperatures in winter, exposure to sunlight in summer, rain and snow), and a large number of batteries are used in series and parallel. Considering reliability and consistency, assuming a car uses 1000 power batteries, ideally, car manufacturers hope that a car model with a scale of 100000 vehicles will not have problems. Ideally, the probability of power battery problems (safety, storage, cycling, etc.) should be less than one in a hundred million (although for the most high-end consumer batteries, Apple also requires suppliers to this level). Considering reliability, power batteries are generally designed with more redundancy, using thicker separators, foils, and casings, so the energy density is about half that of consumer batteries.
2. When developing and designing ordinary consumer lithium-ion batteries, more attention needs to be paid to safety and durability, without the need for long-term reliability (cycling also does not need to be done too well, because it will be replaced in one or two years). Generally, there is no need to use them separately, so there is not much requirement for consistency. However, due to the limited and precious space of consumer smartphones and tablets, consumer lithium-ion batteries have strict requirements for size, capacity, energy density, etc.
3. The difference between power lithium-ion batteries and regular lithium-ion batteries is that for product safety, power batteries have more external protection circuits, heat dissipation layouts, and of course, they also face more harsh conditions (higher external voltage, larger current, and more complex external environment). Consumer batteries have less protection, and they need to rely on the materials and design of the battery to resist various safety hazards on the basis of higher energy density; And high-end consumer mobile phone lithium batteries use the most advanced technology and materials, while power batteries require more advanced process control, consistency control, and quality management.
3、 From a performance perspective:
1. For example, lithium iron phosphate power batteries mainly use lithium iron phosphate LiFeCoPO4 olivine structure as the positive electrode material. Lithium iron phosphate power batteries are a type of battery made of lithium metal or lithium alloy as the positive electrode material and using non-aqueous electrolyte solutions; And ordinary lithium batteries mainly use lithium manganese oxide cathode materials, mainly spinel type lithium manganese oxide materials. Spinel type lithium manganese oxide LiMn2O4 is the cathode material with three-dimensional lithium ion channels first produced by Hunter in 1981; However, with the development trends of lithium-ion battery cathode materials, there may be more high-quality cathode materials to replace current materials. However, regardless of the situation, the safe application of battery materials is more important.
2. What are the main advantages of commonly used lithium batteries in terms of voltage difference between lithium iron phosphate power batteries and lithium batteries? The standard voltage of the lithium iron phosphate power battery platform is 3.2V, fully charged is 3.65V, and the discharge cut-off voltage of the lithium iron phosphate battery cell is 2.0V; The voltage of a regular lithium battery platform is 3.7V, which is 4.2V when fully charged, and the discharge cut-off voltage of the battery cell is 2.7V. In contrast, the voltage of a lithium battery is higher than that of a power battery; Lithium iron phosphate is resistant to overcharging and discharging, and can recover over 80% even if it is briefly discharged to 0; When lithium-ion batteries are placed below 2.5V, irreversible damage can occur.
3. Power lithium batteries do not ignite or explode when punctured, but normal lithium batteries can explode when punctured.
4. Lithium iron phosphate power batteries are resistant to overcharging up to 100% and will not ignite or explode; Ordinary lithium batteries will experience gas evolution and swelling when they reach the specified value.
5. In terms of discharge, the difference between power lithium batteries and ordinary lithium batteries is that lithium iron phosphate power batteries can support a continuous discharge rate of 30C without any safety hazards. Some lithium iron phosphate batteries can achieve an instantaneous current of 600A, while ordinary lithium batteries can support a normal discharge rate of 3C. Continuous high current discharge can cause battery false death.
6. The weight difference between lithium iron phosphate power batteries and lithium batteries: Lithium iron phosphate power batteries of the same volume are nearly twice as heavy as ordinary lithium batteries.
7. Analyzing the difference between power batteries and lithium batteries based on internal resistance: Lithium iron phosphate power batteries of the same volume have much lower internal resistance than ordinary lithium batteries.
8. The difference in capacity between power lithium batteries and ordinary lithium batteries is that the same volume of lithium iron phosphate power batteries has a lower capacity than ordinary lithium batteries, that is, the energy density of the battery made of lithium iron phosphate cathode material is about 60% lower than that of ordinary lithium batteries.
9. The price difference between lithium iron phosphate power batteries and lithium batteries: Lithium iron phosphate power batteries are about 50% more expensive than ordinary lithium batteries.
10. The difference in operating temperature between lithium iron phosphate power batteries and lithium batteries: Compared with lithium batteries, the operating temperature of lithium iron phosphate power batteries is higher, while the operating temperature of lithium batteries is relatively lower by about 5 degrees.
What are the differences between power lithium batteries and ordinary lithium batteries? Investigation and analysis have found that the main differences are in battery material selection and discharge rate application. Different positive electrode materials of lithium batteries have different applications, and if the discharge rate is different, it will be easier to subdivide some application scenarios. Only by understanding the differences between these power lithium batteries and ordinary lithium batteries can we better use them for battery selection and scheme design.