Power battery assembly and electric vehicle comprising the same
A power battery assembly may include a battery circuit and a circuit protecting unit. The circuit protecting unit may be connected in series with the battery circuit. The circuit protecting unit may include a relay and a current sensing unit connected in series with the battery circuit. A switching unit is connected with the relay for controlling the switching of the relay, and a controller is connected with the switching unit and to the current sensing unit to control switching on or switching off the switching unit based on comparison of the current value detected by the current sensing unit, and sent to the controller with a first predetermined current value.
1. A power battery assembly, comprising:
a battery circuit having a plurality of battery modules;
a circuit protecting unit connected in series with the battery circuit, the circuit protecting unit having:
a relay and a current sensing unit connected in series with the battery circuit, the current sensing unit configured to detect a value of a current passing through the relay;
a switching unit connected with the relay for controlling the relay;
a controller connected with the switching unit and to the current sensing unit, and configured to control switching on or off the switching unit based on comparison of the value of the current detected by the current sensing unit with a first predetermined current value; and
wherein if the value of the current is greater than the first predetermined current value and current flow lasts for at least a first predetermined time period, the controller switches off the switching unit, so that the relay is switched off.
2. The power battery assembly of claim 1 , further comprising:
a power source configured to power the relay, the controller, and the current sensing unit, wherein the switching unit is connected in series between the power source and the relay.
3. The power battery assembly of claim 1 , wherein the relay, the controller, and the current sensing unit are powered by at least one of the plurality of the battery modules, wherein the switching unit is connected in series between the at least one of the plurality of the battery modules and the relay.
4. The power battery assembly of claim 1 , wherein the switching unit comprises:
a first MOSFET and a second MOSFET connected in series, with grid electrodes thereof connected with output terminals of the controller, respectively.
5. The power battery assembly of claim 1 , wherein the current sensing unit is a Hall-effect sensor.
6. The power battery assembly of claim 5 , wherein the Hall-effect sensor comprises:
a first lead supporting member formed with an aperture through which a first lead connecting the relay with the battery circuit via the Hall sensor passes; and
a first elastic washer provided between the aperture and the first lead passing therethrough.
7. The power battery assembly of claim 1 , further comprising:
a battery supporting tray configured to support the battery modules;
a lead supporting bracket configured to support and fix a second lead connecting the relay with the battery circuit; and
wherein
the lead supporting bracket is supported on the battery supporting tray.
8. The power battery assembly of claim 7 , wherein the lead supporting bracket comprises:
a base fixed on the battery supporting tray;
a lower semi-ring fixed to the base;
an upper semi-ring mated with the lower semi-ring via flanges formed on the upper and lower semi-rings, respectively; and
wherein
a second elastic washer is provided between the second lead and an opening formed by the mated lower and upper semi-rings.
9. The power battery assembly of claim 1 , wherein a switch is electrically connected in series between the circuit protecting unit and the battery circuit.
10. The power battery assembly of claim 1 , wherein the switching unit is switched off under the control of the controller if the current detected by the current sensing unit has a value larger than a second predetermined current value, and the second predetermined current value is greater than the first predetermined current value, and current flow lasts for at least a second predetermined time period.
11. A power battery assembly for an electric vehicle, comprising:
a battery circuit having a plurality of battery modules;
a circuit protecting unit connected with the battery circuit, the circuit protecting unit having:
a relay and a current sensing unit coupled in series with the battery circuit, the current sensing unit configured to detect a value of a current passing through the relay,
a switching unit connected with the relay configured to control the relay;
a controller connected with the switching unit and to the current sensing unit, an configured to control switching on or off the switching unit; and
wherein if the value of the current is greater than a first predetermined current value and current flow lasts for at least a first predetermined time period, the controller switches off the switching unit, so that the relay is switched off.