Battery high voltage sampling circuit and battery management system

A battery high voltage sampling circuit comprising a positive relay, a negative relay, a first positive sampling unit, a first negative sampling unit, a second positive sampling unit, a second negative sampling unit and a reference voltage terminal, wherein:

• a first terminal of the positive relay is connected to a positive electrode of a power battery pack to be detected, a first terminal of the negative relay is connected to a negative electrode of the power battery pack to be detected, and both of the first positive sampling unit and the first negative sampling unit are connected to the reference voltage terminal;
• the first positive sampling unit is configured to acquire a first positive sampled signal at the first terminal of the positive relay;
• the first negative sampling unit is configured to acquire a first negative sampled signal at the first terminal of the negative relay;
• both of the second positive sampling unit and the second negative sampling unit are connected to the reference voltage terminal;
• the second positive sampling unit is configured to acquire a second positive sampled signal of the power battery pack at a second terminal of the positive relay;
• and
• the second negative sampling unit is configured to acquire a second negative sampled signal of the power battery pack at a second terminal of the negative relay.