Device, system and method for detecting voltage of single batteries of serial lithium battery pack

Abstract

The invention discloses a device for detecting voltage of single batteries of a serial lithium battery pack. The device comprises a single-chip, an A / D converter circuit, a voltage reference circuit, a decoder circuit and an upper computer, wherein an I / O port of the single-chip is connected with an input end of the decoder circuit; each path of output end of the decoder circuit is connected with a first pin of an optical coupler in one-to-one correspondence with the decoder circuit respectively; the second pin of the optical coupler is grounded; the fourth pins of the optical couplers are connected with the positive electrodes of the single lithium batteries in one-to-one correspondence with the optical couplers; the third pins of all the optical couplers are connected with one end of a detection resistor; the other end of the detection resistor is connected with the negative end of the serial lithium battery pack and then grounded; and the input end of the A / D converter circuit is connected with a common connection point of the third pins of the optical couplers and the detection resistor, while the output end is connected with the I / O port of the single-chip. The device can quickly realize voltage measurement of the single lithium battery and ensures precise and reliable result. The invention also provides a system and a method for detecting the voltage of the single batteries of the serial lithium battery pack.

Description

technical field [0001] The invention relates to the field of voltage detection of battery packs, in particular to a device for voltage detection of single cells of lithium battery packs in series, a detection system and a detection method. Background technique [0002] At present, lithium battery packs as the power source of electric vehicles and hybrid electric vehicles are composed of multiple lithium batteries connected in series to achieve the required voltage. The electric vehicle or hybrid lithium battery pack used in this system consists of 96 lithium batteries, which are divided into 6 groups. One group has 16 single lithium batteries. In this battery, multiple batteries are connected together to supply power to the load. Since the lithium batteries cannot be exactly the same when they are manufactured, the performance indicators cannot be exactly the same, so the capacity and life of each lithium battery are also different during use, and the working status of a sin...

AI Technical Summary

Problems solved by technology

The electric vehicle or hybrid lithium battery pack used in this system consists of 96 lithium batteries, which are divided into 6 groups. One group has 16 single lithium batteries. In this battery, multiple batteries are connected together to supply power to the load. Since the lithium batteries cannot be exactly the same when they are manufactured, the performance indicators cannot be exactly the same, so the capacity and life of each lithium battery are also different during use, and the working status of a single battery cannot be determined based on the voltage value of a unit

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