Lithium-ion power battery

Abstract

The invention relates to a lithium-ion power battery, comprising a battery protection board (15). A negative pole output port B- of a detection circuit chip (31) of the battery protection board (15) is electrically connected with a negative pole connecting terminal (21-1); a positive pole output port B+ is electrically connected with a positive pole connecting terminal (22-1). Three ends of a power tube (32) are electrically connected with the negative pole connecting terminal (21-1), an output port M of the detection circuit chip (31) and one end of an equalizing resistor (15-3) respectively; the other end of the equalizing resistor (15-3) is electrically connected with the positive pole connecting terminal (22-1). A temperature relay (15-1) is provided with two output ports D. Two pins at the input end of a photo-coupler relay (15-2) are electrically connected with two output ports of the detection circuit chip (31) respectively; A and B at the other end of the photo-coupler relay (15-2) are two output ports. The lithium-ion power battery features strong protection functions, low cost, simple structure and low fault rate.

Description

technical field [0001] The invention relates to a rechargeable battery, in particular to a lithium-ion power battery, which belongs to the field of power batteries and is mainly used in various hybrid vehicles and pure electric vehicles using lithium-ion power batteries as power sources. Background technique [0002] At present, there are two main structures of lithium-ion power batteries. One is a rolled-type lithium-ion power battery in which the rolled batteries are packaged in a circular or square casing, but the heat dissipation of the batteries during the working process of this battery is only Relying on the gas convection exchange in the internal space and the heat conduction of a very small part of the medium, this structure cannot effectively solve the heat dissipation problem, which makes this structure unable to achieve a large capacity (only about 10Ah) lithium-ion power battery . Even if some manufacturers can increase the capacity, the battery capacity will q...

AI Technical Summary

Problems solved by technology

Present this laminated lithium-ion power battery has the following defects: (1), battery self-protection function is poor

Since the lithium-ion power battery has no protective structure, when the single lithium-ion power battery forms a battery pack, the damage of the single lithium-ion power battery will cause the capacity of each single battery combined in series to be inconsistent, so that the selected Due to the serious discrepancy of the single battery capacity, the battery pack is out of balance, which shortens the service life of the battery pack due to the early damage of the single battery, resulting in a great waste of energy and an increase in cost. In order to make up for this Defects The current method used is: when the batteries that make up the battery pack exceed two cells, the battery pack will add an external battery management system connected to the external control circuit to ensure that even if the single battery is overheated, overcharged, etc. case the safety of the entire battery pack

However, adding an external battery management system brings serious problems: First, the price of the control chip in the external battery management system is more than 5,000 yuan, and the price of the entire external battery management system is more than 15,000 yuan. The cost is very high. The number of battery cells in the battery pack reaches hundreds, adding an external battery management system, the average cost of each single battery is more than 50 yuan, and the number of battery cells in the battery pack is only a few, increasing An external battery management system costs thousands of yuan per single battery on average, and the cost of using the single battery is very expensive. The high cost of the external battery management system prevents many users from using it. It also greatly reduces the safety and versatility of use; the second is that the connection is complicated and there are too many connection points. Calculated on the basis of a battery pack composed of n single batteries connected in series, the lead-out connection line connected to the external battery management system is n+1, such as a battery pack composed of 100 single cells connected in series, there are 101 connecting wires. It is conceivable that the wiring is cumbersome, difficult and costly, and many connection points will cause Faults occur frequently, which brings inconvenience to maintenance and use

Images