Search

EP-4741213-A1 - ALTERNATING CURRENT BATTERY HEATING

EP4741213A1EP 4741213 A1EP4741213 A1EP 4741213A1EP-4741213-A1

Abstract

A system for managing a battery pack of an electric vehicle includes a sensor and a controller. The sensor is configured to detect a temperature associated with the battery pack. The controller is configured to transmit a request to a charger based on a sensor signal from the sensor, and provide at least a portion of alternating current associated with the request and received from the charger to at least a first battery cell of the battery pack such that heat is generated based on an internal resistance of the first battery cell to increase a temperature associated with the first battery cell. Related electric vehicles, methods, and chargers are disclosed.

Inventors

  • PATEL, Saiyam
  • SANKARANARAYANAN, Vivek
  • LIAO, Zitao
  • JOHN, Ben
  • GUO, Owen
  • MUELLER, SEBASTIAN
  • TAO, Alan
  • ESSADAOUI, Zakaria

Assignees

  • Tesla, Inc.

Dates

Publication Date
20260513
Application Date
20251104

Claims (15)

  1. A system for managing a battery pack of an electric vehicle, the system comprising: a sensor configured to detect a temperature associated with the battery pack; and a controller in communication with the sensor, the controller configured to: transmit a request to a charger based on a sensor signal from the sensor; and provide at least a portion of alternating current associated with the request and received from the charger to at least a first battery cell of the battery pack such that heat is generated based on an internal resistance of the first battery cell to increase a temperature associated with the first battery cell.
  2. The system of Claim 1, wherein the controller is configured to transmit the request to the charger in response to determining, based on the sensor signal, that the temperature associated with the battery pack satisfies a threshold.
  3. The system of Claim 1, wherein the request specifies at least one of an amplitude, a frequency, or a direct current (DC) offset for the alternating current.
  4. The system of Claim 3, wherein the controller is configured to determine at least one of the amplitude, the frequency, or the DC offset based on at least one of: a cell type of the battery pack, the temperature associated with the battery pack, or a state of charge of the battery pack.
  5. The system of Claim 1, wherein a frequency of the alternating current is in a range from 80 Hertz (Hz) to 500 Hz, or wherein an amplitude of the alternating current is in a range from 100 Amperes to 1000 Amperes, or wherein the controller is configured to monitor the alternating current and transmit an updated request based on monitoring the alternating current.
  6. An electric vehicle comprising: a plurality of battery cells comprising a first battery cell; and a battery management system configured to: detect a condition associated with the plurality of battery cells; in response to detecting the condition, transmit a request to a charger; and provide alternating current associated with the request and received from the charger to at least the first battery cell such that an internal resistance of the first battery cell and the alternating current increase a temperature associated with the first battery cell.
  7. The electric vehicle of Claim 6, wherein the condition comprises at least one of: a temperature associated with the plurality of battery cells, a state of charge of the plurality of battery cells, or a cell type of the plurality of battery cells.
  8. The electric vehicle of Claim 6, wherein the request specifies a direct current (DC) offset for the alternating current, and wherein the battery management system determines the DC offset based at least in part on a temperature associated with the plurality of battery cells.
  9. The electric vehicle of Claim 8, wherein the battery management system is configured to provide the alternating current to the plurality of battery cells to charge at least one of the plurality of battery cells, or further comprising one or more other components, wherein the battery management system provides alternating current to power the one or more other components, and wherein the one or more other components comprise at least one of a drive unit, a compressor, or a power conversion system.
  10. The electric vehicle of Claim 6, wherein the request specifies an amplitude and a DC offset for the alternating current, and wherein the battery management system is configured to determine the amplitude and the DC offset based at least in part on the condition.
  11. The electric vehicle of Claim 6, wherein the battery management system is configured to: monitor an amplitude of the alternating current to generate a monitor signal; generate, based on the monitor signal, an updated request for adjusting the amplitude of the alternating current; and transmit the updated request to the charger.
  12. A method for managing a battery pack, the method comprising: detecting a temperature associated with the battery pack; transmitting a request to a charger based on the temperature, the request identifying an alternating current waveform; and providing at least a portion of alternating current associated with the request and received from the charger to at least a first battery cell of the battery pack such that heat is generated based on an internal resistance of the first battery cell to increase the temperature associated with the first battery cell.
  13. The method of Claim 12, further comprising: monitoring an amplitude of the alternating current to generate a monitor signal; and generating, based on the monitor signal, and transmitting an updated request to the charger for adjusting the amplitude of the alternating current.
  14. The method of Claim 12, further comprising: determining that the temperature associated with the battery pack satisfies a threshold, wherein the request is transmitted in response to determining that the temperature associated with the battery pack satisfies the threshold.
  15. The method of Claim 12, further comprising: determining an amplitude, a frequency, and a DC offset based on at least one of: a cell type of the battery pack, the temperature associated with the battery pack, and a state of charge of the battery pack, wherein the alternating current waveform indicates the amplitude, the frequency, and the DC offset, or further comprising: providing the alternating current to power a drive unit, a compressor, or a power conversion system of an electric vehicle, or wherein a frequency of the alternating current is between 80 Hz to 500 Hz.

Description

CROSS-REFERENCE TO PRIORITY APPLICATIONS This application claims priority to U.S. Patent Application No. 19/244520, entitled "ALTERNATING CURRENT BATTERY HEATING," filed on June 20, 2025, which claims priority to U.S. Provisional Patent Application No. 63/717,719, entitled "ALTERNATING CURRENT BATTERY HEATING," filed on November 7, 2024, the entire disclosures of each of which are hereby incorporated by reference in their entireties and for all purposes. TECHNICAL FIELD The present disclosure relates to heating batteries. More specifically, embodiments of the present disclosure relate to methods and systems for heating battery packs using alternating current (AC). BACKGROUND Electric vehicles can experience reduced performance in cold weather conditions. For example, battery packs used in electric vehicles can face challenges when being charged at low temperatures (e.g., below 0°C). Under certain low temperature conditions, vehicles may not be able to charge their battery packs, which can result in long wait times at charging stations and some vehicles losing power entirely. Further, charging at low temperatures can lead to battery cell degradation and lithium plating, which can impact energy storage system life and performance. SUMMARY OF CERTAIN INVENTIVE ASPECTS The systems, methods and devices of this disclosure each have several innovative embodiments, no single one of which is solely responsible for all of the desirable attributes disclosed herein. Details of one or more implementations of the subject matter described in this specification are set forth in the accompanying drawings and the description below. In some aspects, the techniques described herein relate to a system for managing a battery pack of an electric vehicle, the system including: a sensor configured to detect a temperature associated with the battery pack; and a controller in communication with the sensor, the controller configured to: transmit a request to a charger based on a sensor signal from the sensor, the request identifying an alternating current waveform; and provide at least a portion of alternating current associated with the request and received from the charger to at least a first battery cell of the battery pack such that heat is generated based on an internal resistance of the first battery cell to increase a temperature associated with the first battery cell. In some aspects, the techniques described herein relate to a system, wherein the controller is configured to transmit the request to the charger in response to determining, based on the sensor signal, that the temperature associated with the battery pack satisfies a threshold. In some aspects, the techniques described herein relate to a system, wherein the request specifies at least one of an amplitude, a frequency, or a direct current (DC) offset for the alternating current. In some aspects, the techniques described herein relate to a system, wherein the controller is configured to determine at least one of the amplitude, the frequency, or the DC offset based on at least one of: a cell type of the battery pack, the temperature associated with the battery pack, or a state of charge of the battery pack. In some aspects, the techniques described herein relate to a system, wherein a frequency of the alternating current is in a range from 80 Hertz (Hz) to 500 Hz. In some aspects, the techniques described herein relate to a system, wherein an amplitude of the alternating current is in a range from 100 Amperes to 1000 Amperes. In some aspects, the techniques described herein relate to a system, wherein the controller is configured to monitor the alternating current and transmit an updated request based on monitoring the alternating current. In some aspects, the techniques described herein relate to an electric vehicle including: a plurality of battery cells including a first battery cell; and a battery management system configured to: detect a condition associated with the plurality of battery cells; in response to detecting the condition, transmit a request to a charger; and provide at least a portion of alternating current associated with the request and received from the charger to at least the first battery cell such that an internal resistance of the first battery cell and the alternating current increase a temperature associated with the first battery cell. In some aspects, the techniques described herein relate to an electric vehicle, wherein the condition includes at least one of: a temperature associated with the plurality of battery cells, a state of charge of the plurality of battery cells, or a cell type of the plurality of battery cells. In some aspects, the techniques described herein relate to an electric vehicle, wherein the request specifies a direct current (DC) offset for the alternating current, and wherein the battery management system determines the DC offset based at least in part on a temperature associated with the plurality of battery cells. I