The difference between metal lithium battery and lithium ion battery

Lithium-ion battery introduction

Lithium-ion battery: It is a secondary battery (rechargeable battery) that mainly relies on lithium ions to move between the positive and negative electrodes to work. During the charging and discharging process, Li+ intercalates and deintercalates back and forth between the two electrodes: when charging, Li+ is deintercalated from the positive electrode, intercalated into the negative electrode through the electrolyte, and the negative electrode is in a lithium-rich state; the opposite is true during discharge.

(1) Positive electrode—the active material is generally lithium manganese oxide or lithium cobalt oxide, nickel-cobalt lithium manganate material, electric bicycles generally use nickel-cobalt lithium manganate (commonly known as ternary) or ternary + a small amount of lithium manganate, pure Lithium manganese oxide and lithium iron phosphate are gradually fading out due to their large size, poor performance or high cost. Electrolytic aluminum foil with a thickness of 10--20 microns is used for the conductive electrode fluid.

(2) Diaphragm - a specially shaped polymer film with a microporous structure that allows lithium ions to pass through freely, but electrons cannot pass through.

(3) Negative electrode - the active material is graphite, or carbon with a similar graphite structure, and the conductive current collector uses electrolytic copper foil with a thickness of 7-15 microns.

(4) Organic electrolyte - a carbonate solvent in which lithium hexafluorophosphate is dissolved, and a gel-like electrolyte for polymers.

(5) Battery shells - divided into steel shells (square type is rarely used), aluminum shells, nickel-plated iron shells (used for cylindrical batteries), aluminum-plastic film (soft packaging), etc., as well as battery caps, which are also positive Negative terminal.

What is the difference between metal lithium battery and lithium ion battery?

How Lithium-Ion Batteries Work

Lithium-ion batteries use carbon materials as the negative electrode and lithium-containing compounds as the positive electrode. There is no lithium metal, only lithium ions. This is the lithium-ion battery. Lithium-ion battery refers to the general term for batteries with lithium-ion intercalation compounds as positive electrode materials. The charging and discharging process of lithium-ion batteries is the intercalation and deintercalation process of lithium ions. During the intercalation and deintercalation process of lithium ions, it is accompanied by the intercalation and deintercalation of electrons equivalent to lithium ions (the positive electrode is customarily represented by intercalation or deintercalation, while the negative electrode is represented by insertion or deintercalation). During the charging and discharging process, lithium ions intercalate/deintercalate and intercalate/deintercalate back and forth between the positive and negative electrodes, which is vividly called "rocking chair battery".

When the battery is charged, lithium ions are generated on the positive electrode of the battery, and the generated lithium ions move to the negative electrode through the electrolyte. The carbon used as the negative electrode has a layered structure, and it has many micropores. Lithium ions that reach the negative electrode are embedded in the micropores of the carbon layer. The more lithium ions are embedded, the higher the charging capacity. Similarly, when the battery is discharged (that is, the process in which we use the battery), the lithium ions embedded in the carbon layer of the negative electrode come out and move back to the positive electrode. The more lithium ions returned to the positive electrode, the higher the discharge capacity.

Generally, the charging current of lithium batteries is set between 0.2C and 1C. The larger the current, the faster the charging, and the greater the heat generation of the battery. Moreover, the capacity is not full enough for charging with an excessive current, because the electrochemical reaction inside the battery takes time. Just like pouring beer, if you pour it too quickly, it will produce foam, which will make you dissatisfied.

What is the difference between metal lithium battery and lithium ion battery?

Advantages of lithium-ion batteries

1) High voltage

The working voltage of a single battery is as high as 3.7-3.8V (3.2V for lithium iron phosphate), which is three times that of Ni-Cd and Ni-MH batteries.

2) Larger specific energy

The actual specific energy that can be achieved is about 555Wh/kg, that is, the specific capacity of the material can reach more than 150mAh/g (3--4 times that of Ni-Cd, 2--3 times that of Ni-MH), which is close to its  About 88% of the value.

3) Long cycle life

Generally, it can reach more than 500 times, or even more than 1000 times, and the lithium iron phosphate can reach more than 2000 times. For electrical appliances with low current discharge, the service life of the battery will double the competitiveness of the electrical appliances.

4) Good safety performance

No pollution, no memory effect. Lithium battery, the predecessor of Li-ion, because metal lithium is easy to form dendrites and short-circuit, which reduces its application field: Li-ion does not contain cadmium, lead, mercury and other elements that pollute the environment: some processes (such as sintering type ) Ni-Cd batteries have a major disadvantage of "memory effect", which seriously restricts the use of batteries, but Li-ion does not have this problem at all.

5) Small self-discharge

The self-discharge rate of fully charged Li-ion at room temperature after storage for 1 month is about 2%, which is much lower than 25-30% of Ni-Cd and 30-35% of Ni-MH.

6) Fast charging

1C charging for 30 minutes can reach more than 80% of the nominal capacity, and the iron-phosphorus battery can be charged to 90% of the nominal capacity in 10 minutes.

7) Working temperature

The working temperature is -25~45°C. With the improvement of electrolyte and positive electrode, it is expected to be extended to -40~70°C.

What is the difference between metal lithium battery and lithium ion battery?

Lithium-ion battery disadvantages

senescence

Unlike other rechargeable batteries, the capacity of lithium-ion batteries will slowly decline, which is related to the number of uses and temperature. This decline phenomenon can be expressed by a decrease in capacity or an increase in internal resistance.

Recovery rate

About 1% of new ex-factory products need to be recycled for various reasons.

intolerance to overcharging

When overcharging, the excessively intercalated lithium ions will be permanently fixed in the crystal lattice and cannot be released again, resulting in short battery life.

intolerance to overdischarge

During over-discharge, the electrode deintercalates too many lithium ions, which can lead to the collapse of the crystal lattice, thereby shortening the life.

What is the difference between metal lithium battery and lithium ion battery?

Lithium metal battery

Lithium battery is a kind of energy storage battery using metallic lithium as the electrode. It has a very high specific energy. It was divided into disposable batteries and rechargeable lithium batteries in the early days. However, after the accident of rechargeable lithium batteries, it is rarely seen in the civilian market. Rechargeable lithium battery. Lithium-ion rechargeable batteries actually use the concentration difference of lithium ions for energy storage and discharge, and there is no metallic lithium in the battery.

The principle of metal lithium battery is the same as that of ordinary dry battery. It uses metal lithium as an electrode, and generates electricity through the corrosion or oxidation of metal lithium. It is useless when it is used up and cannot be charged.

The difference between metal lithium battery and lithium ion battery

The main difference is that metal lithium batteries are disposable batteries, and lithium-ion batteries are rechargeable cycle batteries! The principle of metal lithium battery is the same as that of ordinary dry battery. It uses metal lithium as the electrode, and generates electricity through the corrosion or oxidation of metal lithium. It will be useless when it is used up and cannot be charged. Lithium-ion batteries generally use lithium cobaltate as the positive electrode. , Carbon is used as the negative electrode, and the electrolyte is filled in the middle to form a channel for ion dissociation, and a diaphragm is used to separate the positive and negative electrodes to prevent short circuit. When charging, due to the action of the electric field, lithium ions swim out of lithium cobalt oxide, pass through the pores in the diaphragm in the electrolyte, and reach the negative electrode to react with carbon to form lithium carbide; the discharge process is the opposite, and lithium ions return to the positive electrode. It is the charging and discharging process of lithium-ion batteries.