Using silicon and phosphorene to develop a new composite for the production of anodes for lithium-ion batteries, this material is highly efficient. Compared to current lithium-ion batteries, the new anode material has increased the charging speed and battery capacity by three and five times, respectively, while also reducing the overall weight of the battery. If silicon is only used as the anode material for batteries, it will result in weaker cycling stability. The negative electrode of existing lithium-ion batteries is composed of carbon based graphene sheets stacked layer by layer, with one lithium atom adapting to six carbon atoms. In order to increase energy storage, scientists have attempted to use silicon instead of carbon, so that silicon can adapt to more lithium, reaching 4 lithium atoms corresponding to 1 silicon atom. However, silicon significantly expands and shrinks during the charging process, leading to rapid rupture and loss of charging capacity. The shape of graphene sheets also restricts the charging rate of batteries. In order to stabilize silicon and maintain maximum charging capacity, they added silicon clusters between graphene sheets, utilizing the elasticity of graphene sheets to match the changes in the number of silicon atoms during battery use, allowing a large number of lithium atoms to be stored in the electrode. The addition of silicon clusters can increase energy density while also reducing the loss of charging capacity caused by silicon expansion and contraction, which can be said to have the best of both worlds
How to improve the capacity of lithium-ion batteries
1. Use active substances with better adhesion and conductivity: This can reduce the content of adhesive and conductive agents in the dressing, thereby increasing the capacity that can be exerted per unit mass of the dressing; In addition, reducing the amount of binder and conductive agent can also improve the compaction and other processing properties of the active material.
2. The self-discharge rate of the lithium-ion battery pack is different, and the voltage is different. First, detect the battery with different voltage, and then replace it with the battery with the same capacity, voltage, self-discharge, internal resistance, etc. of the normal lithium-ion battery pack. Alternatively, use a lithium-ion battery pack voltage differential balance repair instrument.
3. Choosing a material system with better matching performance: Combining materials with poor matching performance not only reduces the cycling performance of lithium-ion batteries, but may also affect the rate performance and even the utilization of positive and negative electrodes; Similarly, when the material matching is better, performance such as performance, cycling, and expansion rate may all be improved.
How to improve the charging speed of lithium-ion batteries
There are many charging methods for lithium-ion batteries, including constant current charging, constant voltage charging, constant current constant voltage charging, variable current charging, pulse charging, intermittent charging, etc.
1. The performance of lithium-ion batteries is influenced by the battery temperature. If the temperature is too low, it will affect the activity of the internal substances in the battery, and if it is too high, it will damage the structure of the internal substances. The allowable range is generally between -20 ℃ and+65 ℃, and when designing, it is generally recommended to choose between 0 ℃ and+60 ℃.
2. The main charging stage of the variable current intermittent charging method adopts an intermittent method of gradually decreasing current under limited charging voltage conditions to increase the charging current, which accelerates the charging process and shortens the charging time. However, this charging mode circuit is relatively complex and expensive, and is generally only considered for high-power fast charging.
3. Intelligent charging is currently a relatively advanced charging method that determines the charging status of the battery by checking the increment of battery voltage and current, dynamically tracking the acceptable charging current of the battery, and ensuring that the charging current is always near the maximum acceptable charging curve of the battery.