New Energy Storage Device: Capacitive Lithium-ion Battery

High capacity, high power, long life, safety and environmental protection have always been an important direction for the pursuit of power batteries in the new energy field. Lithium-ion batteries have the advantages of high energy density and are the preferred energy storage devices for electric vehicles. However, they have problems such as low power density, poor low-temperature characteristics, and poor cycle life. Super-capacitor is a kind of energy storage device that works on the principle of double-layer. It has the advantages of high power density, good temperature characteristics, and long life. However, compared with lithium-ion batteries, its energy density is low, only about the lithium-ion battery. 5% cannot meet the energy density requirements of electric vehicles.

How to overcome the respective performance deficiencies of lithium-ion batteries and supercapacitors and complement their advantages is a goal pursued by many researchers in the battery field.

First, the design and manufacture of capacitive lithium-ion batteries take into account the impact of frequent high-current impact on battery performance, if the large capacity capacitors in parallel at both ends of the battery, can buffer the impact of high current on the battery, thereby extending the battery cycle life. In addition, if the electrode material of the supercapacitor is combined with the electrode material of the lithium ion battery to coordinate their work, it is equivalent to keep each battery material particle in the protection of the capacitor, and the cycle life of the battery should be more prolonged. Improve battery power characteristics. Based on this consideration, Liaoning Lixin Energy Co., Ltd. independently developed a capacitive lithium-ion battery.

The capacitive lithium-ion battery combines the working principle of the double-layer supercapacitor with the lithium-ion battery. The device has both the principle of double-layer physical energy storage of the supercapacitor and the principle of embedded energy storage of the lithium-ion battery. , which forms a capacitive lithium-ion battery.

Capacitive lithium-ion battery is the real integration of supercapacitors and lithium-ion battery electrode materials to form a unified new energy storage device - "capacitor lithium-ion battery"; at the same time the electrolyte formulation, battery structure, manufacturing Process, raw materials and other aspects are optimized and adjusted to meet the chemical-physical working principle of the device and the need for high-power operation characteristics.

According to different battery materials that are integrated with the super capacitor, the capacitive lithium ion battery can be further divided into a capacitive lithium iron phosphate lithium ion battery, a capacitive lithium manganese oxide lithium ion battery, and a capacitive ternary lithium ion battery. Key technical issues for the development of capacitive lithium-ion batteries include: electrode composition design issues; electrolyte composition design issues; operating voltage matching issues; structural design issues that match performance; application technology issues.

Capacitor battery types cover 1. Electrolytic capacitor + overcapacity: Electrolytic capacitor + EDLC, electrolytic capacitor + tantalum capacitor; 2. Battery + supercapacitor: Lead-acid battery + EDLC (inorganic capacitive lithium-ion battery), nickel-metal hydride battery + EDLC (inorganic capacitor type Lithium-ion battery), lithium-ion battery + supercapacitor (organic capacitor lithium-ion battery). The company's patented products belong to the latter.

Capacitive lithium ion battery main performance:

Energy density: 60Wh/Kg～120Wh/Kg (can be designed);

Power density: 1300W/Kg～3000W/Kg (can be designed);

Cycle life: 2000 to 5000 times (designable);

Charging time: 0.5h ~ 2h (can be designed);

Temperature range: -30°C～60°C;

Operating voltage range: 2.5 ~ 3.6V (designable);

Better safety performance, no environmental pollution.

In January 2012, capacitive lithium-ion battery products passed the scientific and technological achievements appraisal co-chaired by the Science and Technology Department of Liaoning Province and the Economic and Information Technology Commission. An appraisal committee composed of 11 experts, Yang Yusheng and Gu Guoxuan, and director Wang Dongdong of the National 863 Program's Power Battery Testing Center believes that the results are independent and innovative, and maintain a high level of energy density and power density at the same time. Under the circumstances, the cycle life and low temperature performance have reached the international advanced and domestic leading level of similar products.

Capacitive lithium-ion battery is a new power battery with both energy type and power type. It can be widely used in two major areas of drive power and energy storage, such as electric vehicles (pure electric, hybrid), port machinery, and electric motorcycles. , bicycle power supply, various electrical energy storage devices (wind energy, solar energy, electric storage cabinets, etc.), electric tools, and military fields.