High voltage electrical system for battery electric vehicle

Patent metadata

Field	Value
Publication number	US-11827112-B2
Application number	US-202217680694-A
Country	US
Kind code	B2
Filing date	Feb 25, 2022
Priority date	Nov 30, 2020
Publication date	Nov 28, 2023
Grant date	Nov 28, 2023

Abstract

Connection and control concepts for battery packs in a high voltage battery assembly are provided. Parallel, modular configurations permit improved safety, voltage balancing, and redundancy, improving operation and reliability of an associated high voltage electrical vehicle such as a heavy-duty truck.

First claim

What is claimed is:

1. A battery assembly for an electric vehicle, the battery assembly comprising:
a plurality of high-voltage battery packs;
a front power distribution box; and
a rear power distribution box,
wherein the front power distribution box and the rear power distribution box are electrically coupled in parallel with each high-voltage battery pack of the plurality of high-voltage battery packs,
wherein each battery pack is electrically coupled in parallel with each other battery pack, wherein each battery pack is configured to operate at a voltage between 520 volts and 800 volts, and
wherein each battery pack is configured to operate within 12 volts of each of the other battery packs of the plurality of high-voltage battery packs.

2. The battery assembly of claim 1 , further comprising:
a first battery sub-assembly comprising at least two battery packs electrically coupled in parallel to a second battery sub-assembly comprising at least two battery packs.

3. The battery assembly of claim 1 , wherein each of the plurality of battery packs comprises at least eight battery modules electrically coupled in series with one another.

4. The battery assembly of claim 1 , further comprising a sub-assembly wherein the sub-assembly comprises:
a first battery pack having at least two positive HV connectors and two negative HV connectors; and
a second battery pack having at least two positive HV connectors and two negative HV connectors,
wherein the front power distribution box has at least one front positive HV connector and at least one front negative HV connector,
wherein the rear power distribution box has at least one rear positive HV connector and at least one rear negative HV connector,
wherein the at least one front positive HV connector is directly coupled to a first positive HV connector of the first battery pack,
wherein the at least one front negative HV connector is directly coupled to a first negative HV connector of the second battery pack,
wherein the at least one rear positive HV connector is directly coupled to a first positive HV connector of the second battery pack,
wherein the at least one rear negative HV connector is directly coupled to a first negative HV connector of the first battery pack,
wherein a second positive HV connector of the first battery pack is coupled to a second positive HV connector of the second battery pack, and
wherein a second negative HV connector of the first battery pack is coupled to a second negative HV connector of the second battery pack.

5. The battery assembly of claim 4 , wherein the second positive HV connector of the first battery pack is directly coupled to the second positive HV connector of the second battery pack, and wherein the second negative HV connector of the first battery pack is directly coupled to the second negative HV connector of the second battery pack.

6. A method for maintaining voltage in a high voltage (HV) battery assembly for a vehicle, the method comprising:
selecting a current battery pack from the HV battery assembly having a current voltage measurement, wherein the current voltage measurement is closest to a previous voltage measurement, wherein the previous voltage measurement is a voltage measurement of a first previously selected battery pack, and wherein the current battery pack and the previously selected battery pack are configured to operate at a voltage between 520 volts and 800 volts;
determining a difference between the current voltage measurement and the previous voltage measurement;
in the event the difference is less than a pre-determined threshold, activating the current battery pack; and
designating the current battery pack as a second previously selected battery pack.

7. The method of claim 6 , wherein selecting a current battery pack from the HV battery assembly further comprises:
determining if at least one battery pack from the HV battery assembly is activated;
determining if the activated battery pack is designated as the first previously selected battery pack; and
in the event the activated battery pack is designated as the first previously selected battery pack, selecting the current battery pack from the battery assembly having the current voltage measurement.

8. The method of claim 6 , wherein selecting a current battery pack from the HV battery assembly having a current voltage measurement further comprises:
determining an average of voltage measurement of all battery packs in the HV battery assembly;
selecting a first battery pack having a voltage measurement closest to the average voltage measurement;
activating the first battery pack;
designating the first battery pack as the first previously selected battery pack; and
selecting the current battery pack from the HV battery assembly having the current voltage measurement.

9. The method of claim 6 , wherein the pre-determined threshold is a calibratable threshold.

10. The method of claim 6 , wherein the pre-determined threshold is between 10V and 12V.

11. A method of maintaining voltage in a high voltage (HV) battery assembly for a vehicle, the method comprising:
activating a first battery pack from the HV battery assembly, wherein the HV battery assembly comprises a plurality of battery packs, and wherein the first battery pack has a first voltage measurement;
determining a difference between the first voltage measurement and a voltage measurement of each of the remaining battery packs of the plurality of battery packs;
selecting the battery pack having the smallest difference as a second battery pack,
wherein the second battery pack has a second voltage measurement, and wherein the second voltage measurement is, among the voltage measurements of all other battery packs in the battery assembly, closest to the first voltage measurement; and
activating the second battery pack.

12. The method of claim 11 , wherein activating the second battery pack comprises:
determining a difference between the first voltage measurement and the second voltage measurement; and
in the event the difference is less than a pre-determined threshold, activating the second battery pack.

13. The method of claim 12 , wherein the pre-determined threshold is less than 12V.

14. The method of claim 11 , further comprising:
comparing the second voltage measurement to the first voltage measurement;
in the event the second voltage measurement is higher than the first voltage measurement, selecting a third battery pack having a third voltage measurement, wherein the third voltage measurement is closest to the first voltage measurement and lower than the first voltage measurement;
in the event the second voltage measurement is lower than the first voltage measurement, selecting a third battery pack having a third voltage measurement, wherein the third voltage measurement is closest to the first voltage measurement and higher than the first voltage measurement; and
activating the third battery pack.

15. The method of claim 11 , wherein activating the first battery pack further comprises:
determining an average voltage measurement of all battery packs in the HV battery assembly;
selecting the first battery pack with the first voltage measurement, wherein the first voltage measurement is closest to the average voltage measurement; and
activating the first battery pack.

Assignees

• Nikola Corp

Inventors

• Ashraf Umran
• Corona Michael
• Mclemore T Neil
• Sarkissian Varoujan

Classifications

• H02J7/82

  Control of state of charge [SOC] · CPC title

• H02J7/60

  including safety or protection arrangements · CPC title

• H02J7/54

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

• B60L50/66 Primary

  Arrangements of batteries · CPC title

• B60L50/64

  Constructional details of batteries specially adapted for electric vehicles · CPC title