Smart battery circuit

Patent metadata

Field	Value
Publication number	US-11233419-B2
Application number	US-201715674098-A
Country	US
Kind code	B2
Filing date	Aug 10, 2017
Priority date	Aug 10, 2017
Publication date	Jan 25, 2022
Grant date	Jan 25, 2022

Abstract

An electrical system may include a power circuit configured to provide a power output, first and second batteries, and first and second switches configured to connect and disconnect the first and second batteries, respectively, to the power output in parallel with one another. The electrical system may also include a controller electrically connected to the first and the second switches, and configured to control operation of the first switch and/or the second switch. The electrical system may also include a load predictor in communication with the controller and configured to predict power demands of an electric load on the power circuit and send a signal indicative of the predicted power demands to the controller, which may activate the first switch and/or the second switch to connect the first battery and/or the second battery to the power output based at least in part on the signal indicative of the predicted load.

First claim

What is claimed is:

1. An electrical system configured to supply electric power to an electric motor of an electric vehicle, the electrical system comprising:
a first battery characterized by a first charge state;
a first switch configured to electrically connect the first battery to, and disconnect the first battery from, a power output of a power circuit;
a second battery characterized by a second charge state, which is lower than the first charge state;
a second switch configured to electrically connect the second battery to, and disconnect the second battery from, the power output of the power circuit;
a third switch and a current limiting device electrically connected in series with each other and in parallel with the second switch, the third switch being configured to electrically connect the second battery to, and disconnect the second battery from, the first battery;
a controller electrically connected to the first switch, the second switch, and the third switch, the controller being configured to control operation of the first switch, the second switch, and the third switch;
a planner configured to determine a first predicted trajectory of the electric vehicle to a destination and a second predicted trajectory of the electric vehicle to the destination; and
a load predictor in communication with the planner, the load predictor being configured to:
predict, based on the first predicted trajectory, a first power demand of the electric motor;
predict, based on the second predicted trajectory, a second power demand of the electric motor that is larger than the first power demand; and
send a second signal indicative of the first power demand and the second power demand to the planner;

wherein the planner is configured to determine, based on the first charge state being higher than the second charge state and on the second power demand being larger than the first power demand, to use the first predicted trajectory; and
wherein the controller is configured to, based at least in part on the first charge state being higher than the second charge state and the determining to use the first predicted trajectory:
close the first switch to connect the first battery to the power output of the power circuit while the second switch is open, and
close, while the electric vehicle executes the first predicted trajectory, the third switch to connect the first battery to the second battery to charge the second battery from the first battery until a difference between the first charge state and the second charge state is within a specified threshold.

2. The electrical system of claim 1 , wherein the load predictor is configured to:
receive the first predicted trajectory and the second predicted trajectory from the planner;
receive a third signal from the controller configured to determine power demands associated with the electric motor of the electric vehicle coupled to the power output; and
predict, based at least in part on the third signal from the controller, the first power demand associated with the first predicted trajectory and the second power demand associated with the second predicted trajectory.

3. The electrical system of claim 2 , wherein at least one of the first predicted trajectory or the second predicted trajectory comprise one of a trajectory associated with operation of the electric vehicle on a highway, a trajectory associated with operation of the electric vehicle on a side street, a trajectory associated with operation of the electric vehicle up a hill, or a trajectory associated with operation of the electric vehicle on a street comprising a plurality of traffic signals; and
the load predictor is further configured to:
predict one of a relatively high power demand for the trajectory associated with operation of the electric vehicle on the highway, a relatively low power demand for the trajectory associated with operation of the electric vehicle on the side street, a relatively high power demand associated with the trajectory associated with operation of the electric vehicle up the hill, or a relatively high power demand for the trajectory associated with operation of the electric vehicle on the street comprising the plurality of traffic signals.

4. The electrical system of claim 1 , wherein the controller is configured to control operation of at least one of the first switch or the second switch such that the first charge state and the second charge state are equalized based at least in part on a third signal from the load predictor indicative of the first power demand.

5. The electrical system of claim 1 , further comprising:
a fourth switch and another current limiting device electrically connected in series with each other and in parallel with the first switch.

6. The electrical system of claim 1 , wherein the controller is configured to:
determine that the difference between the first charge state the second charge state is within the specified threshold; and
cause the second switch to connect to the power output.

7. The electrical system of claim 1 , wherein the first power demand is associated with a first time period and the second power demand is associated with a second time period, and
wherein the controller is configured to close, based on the first power demand being smaller than the second power demand, the third switch during the first time period.

8. The electrical system of claim 1 , further comprising:
a first charging circuit electrically coupled in parallel with the first battery to supply charge to the first battery; and
a second charging circuit electrically coupled in parallel with the second battery to supply charge to the second battery,
wherein the controller is configured to operate at least one of the first switch or the second switch to cause charging of at least one of the first battery or the second battery concurrently or independently of one another.

9. The electrical system of claim 8 , wherein the controller is further configured to charge the first battery and the second battery via a single charger.

10. The electrical system of claim 1 , wherein the load predictor is configured to:
receive an information signal indicative of information associated with operation of the electric vehicle comprising at least one of historical information, geographic information, or real-time information; and
predict the power demands of the electric motor based at least in part on the information signal.

11. A method comprising:
receiving a first signal indicating a first charge state of a first battery is higher than a second charge state of a second battery, the first battery and the second battery being configured to provide power to an electric motor of a vehicle;
determining a first predicted trajectory of the vehicle to a destination and a second predicted trajectory of the vehicle to the destination;
predicting, based on the first predicted trajectory, a first power demand;
predicting, based on the second predicted trajectory, a second power demand;
determining the first power demand is lower than the second power demand;
determining, based on the first signal and on the first power demand being lower than the second power demand, to use the first predicted trajectory;
connecting, by a first switch and based at least on the vehicle executing the first predicted trajectory, the first battery to the electric motor, wherein a second switch between the second battery and the electric motor is open while the first predicted trajectory is executed; and
connecting, by a third switch in series with a current limiting device and based at least on the vehicle executing the first predicted trajectory, the first battery to t

Assignees

• Zoox Inc

Inventors

• Hendrix Austin
• Boecker Moritz
• Somers Robert Edward

Classifications

• H02J2105/37

  exchanging power with electric vehicles [EV] or with hybrid electric vehicles [HEV] · CPC title

• H02J7/82

  Control of state of charge [SOC] · CPC title

• H02J7/56

  Active balancing, e.g. using capacitor-based, inductor-based or DC-DC converters · CPC title

• H02J7/54

  Passive balancing, e.g. using resistors or parallel MOSFETs · CPC title

• H02J7/342 Primary

  The other DC source being a battery actively interacting with the first one, i.e. battery to battery charging (with circuits for polarity protection H02J7/68) · CPC title