GB2541413A - Battery cell management - Google Patents
Battery cell management Download PDFInfo
- Publication number
- GB2541413A GB2541413A GB1514656.6A GB201514656A GB2541413A GB 2541413 A GB2541413 A GB 2541413A GB 201514656 A GB201514656 A GB 201514656A GB 2541413 A GB2541413 A GB 2541413A
- Authority
- GB
- United Kingdom
- Prior art keywords
- cell
- cells
- battery
- monitoring unit
- cell monitoring
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
- B60L58/00—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles
- B60L58/10—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries
- B60L58/12—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries responding to state of charge [SoC]
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/36—Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
- G01R31/396—Acquisition or processing of data for testing or for monitoring individual cells or groups of cells within a battery
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
- H02J7/0013—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries acting upon several batteries simultaneously or sequentially
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
- H02J7/0047—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries with monitoring or indicating devices or circuits
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
- H02J7/14—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries for charging batteries from dynamo-electric generators driven at varying speed, e.g. on vehicle
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
- H02J7/0029—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries with safety or protection devices or circuits
- H02J7/00306—Overdischarge protection
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
- H02J7/0047—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries with monitoring or indicating devices or circuits
- H02J7/0048—Detection of remaining charge capacity or state of charge [SOC]
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/60—Other road transportation technologies with climate change mitigation effect
- Y02T10/70—Energy storage systems for electromobility, e.g. batteries
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T90/00—Enabling technologies or technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02T90/10—Technologies relating to charging of electric vehicles
- Y02T90/16—Information or communication technologies improving the operation of electric vehicles
Abstract
A battery system, suitable for use in electric vehicles or stationary power applications, comprises a plurality of series connected cells 101a-c forming a battery string 105 connected in series with a power line, and a plurality of cell monitoring units 102a-c connected in parallel with one or more of the series connected cells. A battery management unit 104 is connected to opposite ends of the battery string and communicates over the power line 103 with the cell monitoring units, each of which may transmit cell condition information. Each series connected cell may be connected in parallel with further cells, and each cell monitoring unit may transmit information including cell voltage, temperature, charge or discharge state and impedance. In an alternate battery system, each cell monitoring unit comprises a first control module (301a-c, figure 3) to monitor a cell voltage, and a second control module (302a-c, figure 3) to disconnect the first control module if the cell voltage falls below a predetermined level.
Description
BATTERY CELL MANAGEMENT Field of the Invention
The invention relates to management of cells in a battery string, for example for use in electric vehicle applications or in stationary power applications.
Background
Modern electrically powered vehicles require battery cell management to ensure the safe and efficient use of cells that make up a battery string. A typical battery string for an electrically powered vehicle, which is made up of a number of series connected cells or cell blocks, may provide a DC operating voltage in the region of 60 to 650 V, depending on the type and configuration of the vehicle. The battery string will therefore require numerous cells connected in series to make up the required voltage, and will require cells to be connected in parallel as cell blocks to make up the required operating current. Additionally, battery strings may be connected in parallel. It is important that each of these cells or cell blocks are maintained within nominal operating conditions, such as cell voltage, temperature and impedance, otherwise operation of the battery string may deteriorate. Impedance can be monitored but is relatively difficult to control, as it is largely a feature of cell chemistry and manufacturing. Monitoring the conditions of individual cells in such a battery string is not a trivial task, and may require many electrical connections to be made throughout a battery string.
An example of a system for monitoring large battery strings is disclosed in US 2010/196748 Al, in which a battery string comprising a plurality of cells includes a plurality of wireless sensor nodes, each electrically connected to a corresponding one of the plurality of cells. Each wireless sensor node includes a sensor circuit for measuring individual cell performance characteristics. Cell-specific performance data is wirelessly transmitted to a vehicle battery management system to determine the state of charge, state of health and remaining useful life data for the overall battery string. A problem with using wireless data transmission, however, is that in-vehicle wireless communications are generally susceptible to noise and may interfere with external systems.
Summary
In accordance with a first aspect there is provided a battery system comprising: a plurality of cells connected in series with a power line to form a battery string; a plurality of cell monitoring units, each cell monitoring unit connected in parallel with a respective one or more of the plurality of series connected cells; and a battery management unit connected between opposing ends of the battery string, wherein each cell monitoring unit is configured to send and receive communication signals to and from the battery management unit along the power line.
Each cell monitoring unit may be configured to transmit communications to the battery management unit indicating a condition of a respective cell. The condition may include one or more of: a voltage; a temperature; a charge state; an impedance; and a depth of discharge of the cell.
Each cell of the battery system may be connected in parallel with one or more further cells, forming a cell block.
The battery management unit may be configured to poll each cell monitoring unit for a status of each respective one or more of the plurality of cells by sending to each cell monitoring unit a request signal having a time stamp, each cell monitoring unit configured to respond to the request signal by sending status information corresponding to the time stamp. The status information sent by each cell monitoring unit may include data sampled at a time indicated by the time stamp.
The request signal may comprise a current measurement and each cell monitoring unit may be configured to respond to the request signal with a cell impedance measurement calculated using the current measurement.
Each cell monitoring unit may be configured to respond to the request signal with a response signal indicating one or more of: a voltage; a temperature; an impedance; a state of charge; and a depth of discharge of a corresponding one or more of the plurality of cells or cell blocks.
Each cell monitoring unit may be configured to continuously monitor a corresponding one or more of the plurality of cells and store data indicating a status of the one or more of the plurality of cells in a buffer along with a time stamp. Each cell monitoring unit may also be configured to respond to the request signal from the battery management unit with stored data having the time stamp from a previous request signal. The stored data may include one or more of an impedance, a state of charge and a depth of discharge.
In accordance with a second aspect there is provided a battery system comprising: a plurality of cells connected in series to form a battery string; a plurality of cell monitoring units, each cell monitoring unit connected to a respective one or more of the plurality of cells, each cell monitoring unit comprising first and second control modules, the first control module configured to monitor a voltage of the corresponding one or more of the plurality of cells and provide a cell voltage indication, the second control module configured to disconnect the first control module from the corresponding one or more of the plurality of cells if the cell voltage indication falls below a predetermined level·
The battery system may comprise a battery management unit connected to the battery string and configured to communicate with each of the first control modules for receiving a cell voltage indication from each first control module, the battery management unit configured to operate the battery string if all of the first control modules are connected to their respective cells and to disable operation of the battery string if any of the first control modules are disconnected from their respective cells.
In accordance with further aspects of the invention there is provided a method of operating a battery system according to either of the above first or second aspects, with corresponding optional or preferable features to those described above.
Detailed Description
The invention is described in further detail below by way of example and with reference to the accompanying drawings, in which: figure 1 is a schematic diagram of an example battery system with a plurality of cells, each cell having a cell monitoring unit; figure 2 is a diagram indicating communications between a battery management unit and a plurality of cell monitoring units in a battery system; and figure 3 is a schematic diagram of an example battery system with a plurality of cells, in which each cell monitoring unit comprises first and second control modules.
As described herein: the term cell refers to an electrochemical cell that can be repeatedly charged and discharged, examples of which are lithium ion cells; a cell monitoring unit is generally a microcontroller-based hardware module having application-specific software installed; a battery string is made up of a number of cells or cell blocks connected in series; and a battery system comprises a battery string together with a master battery controller and a number of cell monitoring units.
Figure 1 illustrates an exemplary battery system 100 comprising a plurality of cells 101a, 101b, 101c connected in series to form a high voltage direct current battery string 105. Each cell has a corresponding cell monitoring unit 102a, 102b, 102c connected in parallel. A cell monitoring unit 102a-c may be connected to one or more cells. One cell monitoring unit may for example, in some embodiments, be connected across two or more cells connected in series. Each cell monitoring unit 102a-c is powered from the corresponding cell lOla-c, and may communicate through the powerline 103.
Although only three cells lOla-c and cell monitoring units 102a-c are illustrated in the exemplary battery system 100, any number of cells may be present, depending on the total voltage required. For example, the battery system 100 may comprise sufficient cells to produce a desired operating voltage, typically in the region of 60V-650V for an electric vehicle. Furthermore, cells lOla-c may each comprise a block of cells connected to each other in parallel to increase the current capacity of the battery system 100.
Each cell monitoring unit 102a-c can communicate with a battery management unit 104, which operates as a master controller. This configuration allows each cell monitoring unit 102a-c to wake in a controlled manner from a low power sleep state, establish a local network and maintain communications during charge or discharge of the battery string 105.
The battery management unit 104 is connected between opposing ends of the string 105 so that is receives the full voltage of the battery string 105.
The cell monitoring units 102a-c may be configured to transmit communications to the battery management unit 104 indicating a condition of their respective connected cell lOla-c. The condition may include information regarding the impedance (Z), depth of discharge (DOD) and/or charge state, which may for example be expressed as a state of charge percentage.
Typically, in order to calculate parameters pertaining to a cell lOla-c, a number of physical parameters have to be measured synchronously. These measurements may be made within the respective cell monitoring device 102a-c and then relevant data communicated to the battery management unit 104 over the powerline 103. The battery management unit 104 may then pass the measurement data to a higher level system at the string interface level.
The cell monitoring units 102a-c and battery monitoring unit 104 communicate over the powerline 103, which may be within a noisy environment with no guarantee of synchronous timing signals between the battery monitoring unit 104 and the cell monitoring units 102a-c. Thus communications or parts of communications may be lost, and variable reception rates for data may occur. A problem is then how to ensure that measurements are made synchronously, when transmissions between each cell monitoring unit and the battery management unit may be intermittent. This problem may be addressed by allowing for buffering of measurement data in each cell monitoring unit and retrieval of samples from the buffer in a deterministic way. In this way, an accurate calculation of parameters such as Z and SOC(%) may be permitted, as described in more detail below.
Figure 2 illustrates example communications between the battery monitoring unit 104 and two cell monitoring units 102a and 102b in a system of the type illustrated in figure 1. Only two cell monitoring units 102a, 102b are illustrated, but it is to be understood that the illustration can be extended to any number of cell monitoring units. In the illustrated embodiment, battery monitoring unit 104 polls an individually addressed cell monitoring unit, sending a request signal 201a including a global time stamp to the series of cell monitoring units 102a-c (only two of which, 102a, 102b, are shown).
In the illustrated example, battery monitoring unit 104 polls cell monitoring unit 102a, sending a timestamped request signal 201a via the powerline, identifying the first cell monitoring unit 102a and containing a current value for the time identified by the timestamp. In response to the request signal 201a, the selected cell monitoring unit 102a sends a response signal 202a. The response signal 202a may include status information corresponding to the timestamp received with the request signal 201a, for example voltage and temperature values, together with calculated values corresponding to a previous timestamp, for example impedance, state of charge and depth of discharge.
The current value in the request signal 201a may be measured directly by the battery monitoring unit 104, or, as illustrated in figure 2, may be measured by a current sensor 203, which periodically provides a current measurement 204 to the battery monitoring unit 104. The current will, of course, be the same for each cell lOla-c making up the battery string 105, since the cells lOla-c are connected in series. The voltage across each cell lOla-c may, however, vary from cell to cell depending on the charge state and other parameters that may affect the impedance of each cell lOla-c.
The response signal 202a may comprise a measure of the impedance of the respective cell 101a, calculated using a current measurement from a previously received request signal 201a. For example, previous cell status information may be stored in a buffer by each cell monitoring unit 102a. Upon receipt of the request signal 201a, the cell monitoring unit 102a may retrieve data from its buffer that was recorded at a time corresponding to the global time stamp in the previous request signal 201a. For example, voltage and temperature data of the cell 101a may be stored in the buffer of cell monitoring unit 102a. Voltage data retrieved from the buffer of cell monitoring unit 102a may be combined with the current measurement in the request signal 201a to calculate the impedance of cell 101a at a time corresponding to the time of the global time stamp. Thus the response signal 202a may comprise information about the previous impedance of cell 101a at a time corresponding to the global time stamp in the request signal 201a. The battery system can therefore calculate parameters relating to cells lOla-c sequentially, rather than requiring synchronous measurement, thereby addressing problems of intermittent communications.
Similarly, a previous state of charge and/or depth of discharge of cell 101a may be calculated using the current measurement in the request signal 201a and data stored in the buffer of cell monitoring unit 102a. The response signal 202a may thus comprise information about the state of charge and/or depth of discharge of cell 101a at a time corresponding to the global time stamp in a previous request signal 201a. This information may be in addition to, or instead of, the impedance data discussed above.
In addition to, or instead of, the previous impedance, state of charge, and depth of discharge information, the response signal 202a may comprise information about the present voltage and temperature of cell 101a as measured by cell monitoring unit 102a. Sending the voltage data may be sufficient if the battery management unit 104 is instead configured to calculate the impedance for each cell.
After a preset time interval, which may for example correspond to the maximum latency of the response signal 202a, the current along the powerline may again be measured by the battery monitoring unit 104 or via the current sensor 203 (which may be an integral part of the battery monitoring unit 104). The process described above then repeats. This allows calculations of parameters from data that would have otherwise been sampled synchronously.
The request signal 201a is also received by the other cell monitoring units, such as the second cell monitoring unit 102b illustrated in figure 2. However, since the request signal 201a is only addressed to the first cell monitoring unit 102c, no response signal is provided. The second cell monitoring unit 102b may, however, use the received current measurement to calculate and store an impedance value, ready for being transmitted when a subsequent request for that value is received. A further request signal 201b is sent from the battery management unit 104 along the power line to the cell monitoring units 102a, 102c. This time, the request 201b identifies the second cell monitoring unit 102b. The first cell monitoring unit 102a receives the request, and may use the data contained in the request, but does not respond. The second cell monitoring unit 102b responds to the request 201b by retrieving data from its buffer indicating the calculations performed in response to a previous request and returning these to the battery management unit 104 in a response signal 202b, along with voltage and temperature measurements.
In a general aspect therefore, the battery management unit is configured to periodically send a request to each cell monitoring unit in the battery string via the powerline, the request identifying a selected cell monitoring unit. Each cell monitoring unit is configured to calculate one or more of an impedance value, a state of charge and a depth of discharge based on current and time information provided by the request and to respond to the request, if selected in the request, by providing one or more previously calculated stored values in a response to the battery management unit sent via the powerline. An advantage of this arrangement is that each cell monitoring unit is effectively a time-triggered system that is able to respond quickly to a request by using previously calculated stored values, and only one cell monitoring unit responds to any request, thereby avoiding communication collisions on the powerline resulting from simultaneous transmissions.
An alternative example embodiment of a battery system 300 is illustrated in figure 3. This embodiment involves a similar arrangement of battery management unit 104, cell monitoring units and cells lOla-c, connected via a powerline 103, although other arrangements may be possible. In this case, each cell monitoring unit comprises first and second control modules 301a-c, 302a-c, the first control module 301a-c configured to monitor a voltage of the corresponding cell lOla-c and provide a cell voltage indication. The first control modules 301a-c may also provide other cell information similar to the cell monitoring units described above in relation to the embodiment in figure 1. The second control module 302a-c is configured to disconnect the first control module 301a-c from the corresponding cell lOla-c if the cell voltage indication falls below a predetermined value.
Disconnecting one of the first control modules 301a-c will only generally happen when the battery system 300 has been left unpowered to discharge over a long period of time. If the battery system 300 continues to be uncharged, leaving the first control module connected will reduce the cell voltage further, which can result in damage to the cell due to over-discharge. Disconnecting the first control module therefore prevents further current drain from the cell by the first control module and thereby prevents, or at least slows down, any further deterioration in the condition of the cell. Disconnection will typically involve electrical isolation rather than physical disconnection. The affected cell or cells can then be charged and restored to normal working conditions using a standard charging routine.
The second control modules 302a-c are preferably provided as hardware modules that act as a hardware backup system to the first control modules 301a-c, which are typically controlled using pre-programmed software.
As an example, each of the second control modules 302a-c may be configured to disconnect a corresponding one of the first control modules 301a-c from its corresponding cell lOla-c if the cell voltage drops to 2.14V or below, at which point the cell will enter a minimum power state. No communication with the battery management unit 104 is then possible and no other circuitry is powered until the cell voltage rises to 2.2V.
The battery management unit may be configured to disable operation of the battery system if a cell voltage indication is not received from all of the first control modules 301a-c, since this would indicate that the cell voltage of one or more of the cells 101a-c had fallen below the predetermined value.
An example of a suitable circuit for providing the function described above is the Analog Devices ADP2503/ADP2504 buck-boost DC-to-DC converter, in which the undervoltage lockout function to prevent deep battery discharge may be used.
Other embodiments are within the scope of the invention, which is defined by the appended claims.
Claims (26)
1. A battery system comprising: a plurality of cells connected in series with a power line to form a battery string; a plurality of cell monitoring units, each cell monitoring unit connected in parallel with a respective one or more of the plurality of series connected cells; and a battery management unit connected between opposing ends of the battery string, wherein each cell monitoring unit is configured to send and receive communication signals to and from the battery management unit along the power line.
2. The battery system of claim 1 wherein each cell monitoring unit is configured to transmit communications to the battery management unit indicating a condition of a respective one or more of the plurality of cells.
3. The battery system of claim 2 wherein the condition includes one or more of: a voltage; a temperature; a charge state; an impedance; and a depth of discharge of the respective one or more of the plurality of cells.
4. The battery system of any preceding claim wherein each cell is connected in parallel with one or more further cells.
5. The battery system of claim 1, wherein the battery management unit is configured to poll each cell monitoring unit for a status of each respective one or more of the plurality of cells by sending to each cell monitoring unit a request signal having a time stamp, each cell monitoring unit configured to respond to the request signal by sending status information corresponding to the time stamp.
6. The battery system of claim 5 wherein the request signal comprises a current measurement and each cell monitoring unit is configured to respond to the request signal with a cell impedance measurement calculated from the current measurement.
7. The battery system of claim 5 or claim 6 wherein each cell monitoring unit is configured to respond to the request signal with a response signal indicating one or more of: a voltage; a temperature; an impedance; a state of charge; and a depth of discharge of a corresponding one or more of the plurality of cells.
8. The battery system of any one of claims 5 to 7 wherein each cell monitoring unit is configured to continuously monitor a corresponding one or more of the plurality of cells and store data indicating a status of the one or more of the plurality of cells in a buffer along with a time stamp.
9. The battery system of claim 8 wherein each cell monitoring unit configured to respond to the request signal from the battery management unit with stored data having the time stamp from a previous request signal.
10. The battery system of claim 8 or claim 9 wherein the stored data includes one or more of an impedance, a state of charge and a depth of discharge.
11. A method of operating a battery system according to claim 1, the method comprising transmitting communication signals between the battery management unit and each of the plurality of cell monitoring units along the power line.
12. The method of claim 11 comprising transmitting communications to the battery management unit from each cell monitoring unit along the power line indicating a condition of a respective one or more of the plurality of cells.
13. The method of claim 11 or claim 12 wherein the condition includes one or more of: a voltage; a temperature; a charge state; an impedance; and a depth of discharge of the respective one or more of the plurality of cells.
14. The method of any one of claims 11 to 13 wherein each cell is connected in parallel with one or more further cells.
15. The method of claim 11 wherein the battery management unit polls each cell monitoring unit for a status of each respective one or more of the plurality of cells by sending to each cell monitoring unit a request signal having a time stamp, each cell monitoring unit responding to the request signal by sending status information corresponding to the time stamp.
16. The method of claim 15 wherein the request signal comprises a current measurement and each cell monitoring unit responds to the request signal with a cell impedance measurement calculated from the current measurement.
17. The method of claim 15 or claim 16 wherein each cell monitoring unit responds to the request signal with a response signal indicating one or more of: a voltage; a temperature; an impedance; a state of charge; and a depth of discharge of a corresponding one or more of the plurality of cells.
18. The method of any one of claims 15 to 17 wherein each cell monitoring unit continuously monitors a corresponding one or more of the plurality of cells and stores data indicating a status of the one or more of the plurality of cells in a buffer along with a time stamp.
19. The method of claim 18 wherein each cell monitoring unit responds to the request signal from the battery management unit with stored data having the time stamp from a previous request signal.
20. The method of claim 18 or claim 19 wherein the stored data includes one or more of an impedance, a state of charge and a depth of discharge.
21. A battery system comprising: a plurality of cells connected in series to form a battery string; a plurality of cell monitoring units, each cell monitoring unit connected to a respective one or more of the plurality of cells, each cell monitoring unit comprising first and second control modules, the first control module configured to monitor a voltage of the corresponding cell and provide a cell voltage indication, the second control module configured to disconnect the first control module from the corresponding one or more of the plurality of cells if the cell voltage indication falls below a predetermined level.
22. The battery system of claim 21 comprising a battery management unit connected to the battery string and configured to communicate with each of the first control modules for receiving a cell voltage indication from each first control module, the battery management unit configured to operate the battery string if all of the first control modules are connected to their respective one or more cells and to disable operation of the battery string if any of the first control modules are disconnected from their respective one or more cells.
23. A method of operating a battery system according to claim 21, the method comprising each of the second control modules monitoring a cell voltage indication provided by the respective first control modules, a first control module being disconnected from the respective one or more of the plurality of cells by the respective second control module if the respective second control module detects that the cell voltage indication falls below a predetermined level.
24. The method of claim 23 wherein the battery system comprises a battery management unit connected to the battery string, the battery management unit communicating with each of the first control modules to receive a cell voltage indication from each first control module, the battery management unit operating the battery string if all of the first control modules are connected to their respective one or more cells and disabling operation of the battery string if any of the first control modules are disconnected from their respective one or more cells.
25. A battery system substantially as described herein, with reference to the accompanying drawings.
26. A method of operating a battery system substantially as described herein, with reference to the accompanying drawings.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB1514656.6A GB2541413A (en) | 2015-08-18 | 2015-08-18 | Battery cell management |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB1514656.6A GB2541413A (en) | 2015-08-18 | 2015-08-18 | Battery cell management |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB201514656D0 GB201514656D0 (en) | 2015-09-30 |
| GB2541413A true GB2541413A (en) | 2017-02-22 |
Family
ID=54258785
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB1514656.6A Withdrawn GB2541413A (en) | 2015-08-18 | 2015-08-18 | Battery cell management |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2541413A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108349392A (en) * | 2015-11-04 | 2018-07-31 | 江森自控科技公司 | String control unit automatically configures and failure transmission system and method |
| EP3599473A1 (en) * | 2018-07-27 | 2020-01-29 | Nxp B.V. | Dual-cell supervisor circuit for high-voltage automotive battery packs |
| US20230347787A1 (en) * | 2022-04-29 | 2023-11-02 | Beta Air, Llc | Systems and method for battery monitoring with over charge protection |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20210047138A (en) * | 2019-10-21 | 2021-04-29 | 현대자동차주식회사 | Apparatus and method for detecting battery discharging cause for vehicle |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6133709A (en) * | 1997-01-21 | 2000-10-17 | Metrixx Limited | Signalling system |
| US20120116699A1 (en) * | 2010-11-09 | 2012-05-10 | International Business Machines Corporation | Analyzing and controlling performance in a composite battery module |
| WO2014147896A1 (en) * | 2013-03-22 | 2014-09-25 | ソニー株式会社 | Management device, communication device, management method, and management system |
| EP2783905A2 (en) * | 2013-03-29 | 2014-10-01 | Fujitsu Limited | Battery monitoring system, battery cartridge, battery package, and ridable machine |
| US20150146800A1 (en) * | 2012-05-21 | 2015-05-28 | Robert Bosch Gmbh | Conditioning device and method for conditioning a data channel of a cell of an electrical energy store |
-
2015
- 2015-08-18 GB GB1514656.6A patent/GB2541413A/en not_active Withdrawn
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6133709A (en) * | 1997-01-21 | 2000-10-17 | Metrixx Limited | Signalling system |
| US20120116699A1 (en) * | 2010-11-09 | 2012-05-10 | International Business Machines Corporation | Analyzing and controlling performance in a composite battery module |
| US20150146800A1 (en) * | 2012-05-21 | 2015-05-28 | Robert Bosch Gmbh | Conditioning device and method for conditioning a data channel of a cell of an electrical energy store |
| WO2014147896A1 (en) * | 2013-03-22 | 2014-09-25 | ソニー株式会社 | Management device, communication device, management method, and management system |
| EP2983238A1 (en) * | 2013-03-22 | 2016-02-10 | Sony Corporation | Management device, communication device, management method, and management system |
| EP2783905A2 (en) * | 2013-03-29 | 2014-10-01 | Fujitsu Limited | Battery monitoring system, battery cartridge, battery package, and ridable machine |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108349392A (en) * | 2015-11-04 | 2018-07-31 | 江森自控科技公司 | String control unit automatically configures and failure transmission system and method |
| CN108349392B (en) * | 2015-11-04 | 2022-03-29 | Cps科技控股有限公司 | Automatic configuration and fault transmission system and method for string control unit |
| EP3599473A1 (en) * | 2018-07-27 | 2020-01-29 | Nxp B.V. | Dual-cell supervisor circuit for high-voltage automotive battery packs |
| US11018384B2 (en) | 2018-07-27 | 2021-05-25 | Nxp B.V. | Dual-cell supervisor circuit for high-voltage automotive battery packs |
| US20230347787A1 (en) * | 2022-04-29 | 2023-11-02 | Beta Air, Llc | Systems and method for battery monitoring with over charge protection |
Also Published As
| Publication number | Publication date |
|---|---|
| GB201514656D0 (en) | 2015-09-30 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110546849B (en) | Wireless battery management system and method for protecting battery pack using the same | |
| US6677759B2 (en) | Method and apparatus for high-voltage battery array monitoring sensors network | |
| US9529053B2 (en) | Battery management system and method for determining the charge state battery cells, battery and motor vehicle comprising a battery management system | |
| KR101416798B1 (en) | Battery management system and method with a hierarchical structure | |
| US9088052B2 (en) | Battery multi-series system and communication method thereof | |
| KR101813461B1 (en) | Method for transmitting data in a battery management system | |
| CN203481890U (en) | Lithium battery management system used for communication | |
| CN105071451A (en) | Battery management system | |
| JPWO2015181866A1 (en) | Battery system | |
| GB2541413A (en) | Battery cell management | |
| KR102568627B1 (en) | System and method for checking slave battery management system | |
| CN113748046B (en) | Battery management system, battery management method, battery assembly, and electric vehicle | |
| KR20190106061A (en) | Apparatus and method for estimating state of health of battery rack | |
| CN111025160A (en) | Battery management system and method based on wireless communication | |
| JP7228704B2 (en) | Storage battery device | |
| CN106707216B (en) | Test system of distribution automation terminal battery management | |
| CN107636480B (en) | Parallel monitoring device for battery pack state | |
| US20150185291A1 (en) | Switched capacitor battery unit monitoring system | |
| CN110676520A (en) | Wireless communication battery management system and control method thereof | |
| CN209148854U (en) | Determine device, electrical system and the control module of vehicle low-voltage electric system failure | |
| KR101439233B1 (en) | Battery management system with subsidiary battery | |
| US11880264B2 (en) | BMS recognition system and method | |
| KR20190142152A (en) | Energy storage system including System BMS | |
| CN111077459A (en) | Car as a house power monitoring management system | |
| CN218849578U (en) | Integrated board and household storage system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |