When a lithium battery is discharged, Li+ is deintercalated from the negative electrode and integrated into the positive electrode via the electrolyte. The positive electrode is in a lithium-rich state, that is, the battery will be discharged during. normal use, and the opposite happens during charging.
When the battery is discharged (that is, the process when we use the battery), the lithium ions embedded in the carbon layer of the negative electrode are released and return to the positive electrode. The more lithium ions returned to the positive electrode, the higher the discharge capacity.
Detailed information:
Precautions for using lithium batteries:
1. The discharge current should not be too large
Excessive current will cause the battery to internal heat may cause damagepermanent ages. On mobile phones this is no problem and can be ignored. , the larger the battery discharge current, the smaller the discharge capacity and the voltage drops faster.
2. Never over-discharge
The internal storage of electrical energy in lithium batteries is achieved by a reversible chemical change in electrochemistry. Excessive discharge will make this chemical change irreversible. A reaction occurs, which is why lithium batteries are most concerned about over-discharging. Once the discharge voltage is below 2.7V, the battery can be discarded. Cell phone batteries have a protection circuit installed inside. When the voltage is not low enough to damage the battery, the protection circuit comes into effect and stops discharging.
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The lithium battery of electric vehicle is completely discharged until the lights go out
1. Unload it first: you can. use discharge or resistive discharge method. When using the discharge, it should be at a level where it stops when the power is turned on. For resistance discharge, small electric beads connected to the corresponding voltage can be used to discharge for a long time until the small electric beads are connected and immediately. extinct.
2. Activation: Connect the 12V AC power supply, connect a rectifier diode in series between the battery, and temporarily remove a light-emitting diode from other waste circuits to replace it , and check that it can be formed pulsed DC is equivalent to superposing DC and AC for 90 minutes, then use discharge or resistance discharge, and finally charge using the original method.
Example: When a Canon camera's battery was almost unusable, charging took just a few minutes. After processing, it took 90 minutes to load the number of photos. The value taken was close to the original level, indicating that the battery has expired. The principle is that pulsed direct current can penetrate the capacity of the battery passivation layer and activate it. Initial experiments have proven that charging with pulsed direct current is not only faster, but also extends battery life.
3. Freezing can also make lithium batteriesPool activation.
Due to self-discharge, the voltage gradually decreases when the voltage is lower than the minimum threshold voltagee defined by the lithium battery protection board (generally lithium batteries range from 2.5V). at 3.0 V), the output power will be automatically cut off. At present, a multimeter cannot measure the voltage outside the lithium battery, and a mobile phone or universal charger cannot be used to charge it. This is called battery hibernation.
Charge with a charger slightly higher than the normal charging voltage of the mobile phone, perform strong activation, repair and wake up the lithium battery which is dormant due to excessive self-discharge .
Lithium battery capacity discharge process of electric vehicle
1. The voltage across the lithium battery of the electric vehicle drops quickly in the initial phase. The higher the discharge rate, the faster the voltage drops. .
2. The battery voltage hasLithium in electric vehicles is entering a phase of slow change. This period is called the battery plateau zone. The lower the discharge rate, the longer the plateau area lasts. The higher the platform voltage, the slower the voltage decline. In the actual use of lithium-ion batteries, it is hoped that lithium batteries will work in the platform area as much as possible.
3. When the lithium battery is almost discharged, the lithium battery charging voltage begins to drop sharply until it reaches the discharge cut-off voltage. From the capacity test results, the curved relationship between discharge current and capacity can also be obtained.
The relationship between different discharge currents and capacities of lithium batteries for electric vehicles. The discharge current of lithium batteries will directly affect the actual capacitythe of the battery. The higher the discharge current, the lower the battery capacity, which shows that the higher the discharge current, the shorter the time to reach the final voltage. Therefore, when talking about battery capacity, it is appropriate to specify its discharge current (discharge rate).
Experience in charging and discharging lithium batteries for electric vehicles
Based on the editor's years of experience in using electric vehicles, here are the Most important tips for charging and discharging lithium batteries in electric vehicles. Vehicles during use Yes
1. Charge according to the standard time and procedure indicated in the electric vehicle lithium battery manual, even for the first times.
2. When the electric vehicle finds that the battery is too low, you should try to start charging the battery atlithium of the electric vehicle as soon as possible.
3. According to electric vehicle lithium battery wholesale market experts, activating lithium batteries does not require special methods. Lithium batteries will be activated naturally during normal electric vehicle use. If you insist that it will be fully charged for 12 hours when you first use it, that's actually not scientific.