Electrochemical energy accumulator and balancing method

• US 10,193,356 B2
• Filed: 12/30/2014
• Issued: 01/29/2019
• Est. Priority Date: 01/10/2014
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Butzmann, Stefan
• Primary Examiner(s): Ngo, Brian
• Application Number:
  US15/110,484
• Publication Number:
  US 20160329725A1
• Time in Patent Office: 1,491 Days
• Field of Search: 320107, 320118, 320122, 320134
• CPC Class Codes: B60L 58/12 responding to state of charge [SoC]
• CPC Class Codes: B60L 58/18 of two or more battery modules
• CPC Class Codes: B60L 58/22 Balancing the charge of battery modules
• CPC Class Codes: H01M 10/425 Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing printed circuits H05K1/00
• CPC Class Codes: H01M 2010/4271 Battery management systems including electronic circuits, e.g. control of current or voltage to keep battery in healthy state, cell balancing
• CPC Class Codes: H01M 2220/20 Batteries in motive systems, e.g. vehicle, ship, plane
• CPC Class Codes: H02J 7/0014 Circuits for equalisation of charge between batteries
• CPC Class Codes: H02J 7/0016 using shunting, discharge or bypass circuits
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

An electrochemical energy accumulator (100) and a method for balancing a multiplicity of sections (S1, S2, S3) of electrochemical accumulator modules (10) connected in parallel with one another by means of at least one UniBB module are proposed. In this context, the following steps are carried out: detecting (S100) a first state of charge (I) of a first accumulator module (M1), detecting (S200) a second state of charge (II) of a second accumulator module (M2), wherein the second accumulator module (M2) is a UniBB module, and operating (S300) the second accumulator module (M2) as a power source in order to adapt the first stage of charge (I) and the second state of charge (II) to one another.

Claims

1. A method for balancing a multiplicity of strings of electrochemical storage modules (10) connected in parallel with one another by means of at least one universal buck-boost (UniBB) module and connected by a loading contactor to a load and by a charging contactor to a charger, the method comprising:

identifying (S100) a first state of charge (I) of a first storage module (M1) in a first string of the multiplicity of strings,

identifying (S200) a second state of charge (II) of a second storage module (M2) in a second string of the multiplicity of strings, wherein the second storage module (M2) is a UniBB module,

disconnecting the multiplicity of strings of electrochemical storage modules from the load and the charger, and

operating the first storage module (M1) as a voltage source while the second storage module (M2) is operated as a current source to balance the first state of charge (I) and the second state of charge (II),

wherein the electrochemical storage modules (M1, M2, Mn) further include

(a) electrochemical storage modules which are put into a blocking mode if they belong to strings (S0) not involved in balancing the multiplicity of strings of electrochemical storage modules (10),

(b) electrochemical storage modules which are put into a bypass mode if they belong to strings (S1, S3) involved in balancing the multiplicity of strings of electrochemical storage modules (10), or

both (a) and (b).

2. The method as claimed in claim 1, wherein the first storage module (M1) is also a UniBB module (M).

3. The method as claimed in claim 1, wherein the second state of charge (II) is lower than the first state of charge (I).

4. The method as claimed in claim 1, wherein

the first storage module (M1) is operated in a first operating mode selected from the group consisting of “

regulated”

, “

unregulated”

, “

buck”

, and “

boost”

, and

the second storage module (M2) is operated in a second operating mode selected from the group consisting of “

regulated”

, “

unregulated”

, “

buck”

, and “

boost”

.

5. The method as claimed in claim 1, wherein the first storage module (M1) is operated unregulated and the second storage module (M2) is operated in a boost current source operating mode, or the first storage module (M1) is operated in a buck charging mode and the second storage module (M2) is operated in a current source mode.

6. The method as claimed in claim 1, wherein

if one storage module (M1, M2, Mn) is contained per string (S1, S2, S3), a storage module (M1, M2, Mn) having a highest state of charge is operated as a voltage source and other electrochemical storage modules not put into the blocking mode are operated in a current source mode, and

if more than one storage module (M1, M2, Mn) is contained per string (S1, S2, S3), a storage module (M1, M2, Mn) having a highest state of charge is operated in a current source mode and other electrochemical storage modules not put into the blocking mode or bypass mode are operated in a voltage source mode.

7. The method as claimed in claim 1, wherein when a multiplicity of strings of electrochemical storage modules (10) are connected by the charging contactor to the charger, a charging current impressed into the electrochemical storage modules (10) is controlled depending on a respective state of charge of the storage modules (10) such that a predefined state of charge of the storage modules is substantially attained at an identical point in time.

8. The method as claimed in claim 1, wherein electrochemical storage modules (10) which have attained a predefined maximum voltage are put into the blocking mode.

9. The method as claimed in claim 1, wherein when a multiplicity of strings of electrochemical storage modules (10) are connected by the loading contactor to the load, the strings (S1, S2, S3), depending on their respective average state of charge, are involved in a total current to be supplied of the electrochemical storage modules (10) in order to assume a substantially identical state of charge.

10. An electrochemical energy store (100) comprising

a multiplicity of strings (S1, S2, S3) of electrochemical storage modules (M1, M2, Mn) connected in parallel with one another, and

a processing unit, wherein the processing unit is designed to carry out a method as claimed in claim 1.