Battery module with related devices and methods

Abstract

The present invention relates to a battery module, related devices and methods. More particularly, the present invention relates to a battery module with an improved mechanism of electrically connecting modules to form one or more battery packs and devices and methods that relate to the improved mechanism. In one aspect, the present invention provides a battery module. The module comprises: a top cover that connects to a bottom housing to form a casing; a positive terminal connected to a proximal end of the casing, wherein the end of the positive material is shaped such that it can insert into a sleeve; a negative electrode connected to a distal end of the casing, wherein the negative electrode is housed within the sleeve such that an electrical contact is made when a positive terminal is inserted into the sleeve; and, at least one electrochemical cell connected to the inside surface of the bottom housing.

Description

FIELD OF THE INVENTION

The present invention relates to a battery module, related devices and methods. More particularly, the present invention relates to a battery module with an improved mechanism of electrically connecting modules to form one or more battery packs and devices and methods that relate to the improved mechanism.

BACKGROUND OF THE INVENTION

Large format batteries are typically constructed in modular form. One must first determine what the power and energy storage requirements are for a large format battery or pack; one then designs the battery/pack using available building blocks (i.e., modules). The modules are, in turn, engineered to meet a number of specifications related to the typical battery pack a particular manufacturer produces.

There have been many reports of battery module designs. Examples of such reports include: U.S. application Ser. No. 10/259,122; U.S. application Ser. No. 10/961,232; U.S. application Ser. No. 11/300,306; and, U.S. application Ser. No. 11/434,864.

U.S. application Ser. No. 11/259,122 discusses a battery case that is formed by justaposing a plurality of electrode plate group housing chambers. An electrolyte-impregnated electrode plast group is housed in each of the housing chambers. A side plate is arranged in abutment with each side face of the battery case. The respective side faces are faced with the openings of the electrode plate group housing chambers. This makes it possible to close the openings of the electrode plate group housing chambers. Thus, the cells and the battery module are fabricated concurrently.

U.S. application Ser. No. 10/961,232 discusses a battery module and a combination battery. In this module, the handling of unit cells is facilitated to enhance production efficiency while contributing to a downsized power source. The battery module includes laminate-sheathed cells as unit cells and a retention member for retaining the laminate-sheathed cells. The retention member is configured with a printed-wiring board printed with voltage measurement wirings for measuring voltages of the laminate-sheathed cells.

U.S. application Ser. No. 11/300,306 discusses a battery module including an output breaker that ensures safe and prompt installation of batteries in a system. The battery module includes one or more batteries and a case housing the batteries having output terminals. Each output terminal is connected to a positive or negative electrode of the housed battery. The battery module further includes means for turning on and off the connection between the output terminal and the positive or negative electrode of the battery. The means for turning on and off the connection may include a contact subjected to making and breaking operations and a screw for making and breaking the contact; the screw has an insulator at an interface with the contact.

U.S. application Ser. No. 11/434,864 discusses a battery module that combines a plurality of unit cells. The cells are mounted into a cap structure. The cap structure includes a circuit that electrically connects the unit cells.

Despite the many battery module designs there still exists a need for further, improved battery module designs. That is one object of the present invention.

SUMMARY OF THE INVENTION

The present invention relates to a battery module, related devices and methods. More particularly, the present invention relates to a battery module with an improved mechanism of electrically connecting modules to form one or more battery packs and devices and methods that relate to the improved mechanism.

In one aspect, the present invention provides a battery module. The module includes: a battery module cover that connects to one or more battery module cases to form a housing; a first internal buss bar and power pin connected to a proximal end of the housing, wherein the first internal buss bar and power pin is shaped such that it can insert into a first internal buss bar and power sleeve from a second module; a second internal buss bar and power sleeve connected to a distal end of the housing, wherein the second internal buss bar and power sleeve is shaped such that it can receive a second internal buss bar and power pin from a third module; and, at least one electrochemical cell connected to the inside surface of at least one battery module case.

In another aspect, the present invention provides a large format battery pack. The battery pack includes at least two modules that are electrically connected to one another. When connected, there is sufficient space between the two modules to allow air flow. The modules include: a battery module cover that connects to one or more battery module cases to form a housing; a first internal buss bar and power pin connected to a proximal end of the housing, wherein the first internal buss bar and power pin is shaped such that it can insert into a first internal buss bar and power sleeve from a second module; a second internal buss bar and power sleeve connected to a distal end of the housing, wherein the second internal buss bar and power sleeve is shaped such that it can receive a second internal buss bar and power pin from a third module; and, at least one electrochemical cell connected to the inside surface of at least one battery module case.

In another aspect, the present invention provides a method of reducing the accidental discharge profile associated with assembling a large format battery pack by at least 1 percent. The method includes the steps of assembling the pack with one or more modules, wherein each of the one or more modules include: a battery module cover that connects to one or more battery module cases to form a housing; a first internal buss bar and power pin connected to a proximal end of the housing, wherein the first internal buss bar and power pin is shaped such that it can insert into a first internal buss bar and power sleeve from a second module; a second internal buss bar and power sleeve connected to a distal end of the housing, wherein the second internal buss bar and power sleeve is connected to a distal end of the housing, wherein the second internal buss bar and power sleeve is shaped such that it can receive a second internal buss bar and power pin from a third module; and, at least one electrochemical cell connected to the inside surface of at least one battery module case.

In another aspect, the present invention provides a method of decreasing the number of man hours needed to construct a large format battery pack by at least 2.5 percent. The method comprises assembling the pack with at least twenty modules. Each of the at least twenty modules include: a battery module cover that connects to one or more battery module cases to form a housing; a first internal buss bar and power pin connected to a proximal end of the housing, wherein the first internal buss bar and power pin is shaped such that it can insert into a first internal buss bar and power sleeve from a second module; a second internal buss bar and power sleeve connected to a distal end of the housing, wherein the second internal buss bar and power sleeve is shaped such that it can receive a second internal buss bar and power pin from a third module; and, at least one electrochemical cell connected to the inside surface of at least one battery module case.

In another aspect, the present invention provides a method of increasing the rate at which large format battery packs pass shock and vibration tests as codified in UN 38.3 on lithium ion batteries by at least 1 percent. The method comprises constructing a pack on a substrate using modules; each of the modules include: a battery module cover that connects to one or more battery module cases to form a housing; a first internal buss bar and power pin connected to a proximal end of the housing, wherein the first internal buss bar and power pin is shaped such that it can insert into a first internal buss bar and power sleeve from a second module; a second internal buss bar and power sleeve connected to a distal end of the housing, wherein the second internal buss bar and power sleeve is shaped such that it can receive a second internal buss bar and power pin from a third module; and, at least one electrochemical cell connected to the inside surface of at least one battery module case.

In another aspect, the present invention provides a method of decreasing the cost of constructing an energy storage device that is connected to the electrical grid by at least 1 percent. The method comprises constructing a large format battery pack that is included as part of the energy storage device. The large format battery pack includes at least twenty modules, and each of the modules include: a battery module cover that connects to one or more battery module cases to form a housing; a first internal buss bar and power pin connected to a proximal end of the housing, wherein the first internal buss bar and power pin is shaped such that it can insert into a first internal buss bar and power sleeve from a second module; a second internal buss bar and power sleeve connected to a distal end of the housing, wherein the second internal buss bar and power sleeve is shaped such that it can receive a second internal buss bar and power pin from a third module; and, at least one electrochemical cell connected to the inside surface of at least one battery module case.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 shows an exploded view of a battery module (100) according to the present invention.

FIG. 2 shows an assembled view of the battery module (100) according to the present invention.

FIG. 3 shows a view of an interlocking system (300) to which modules (100) of the present invention have been attached.

FIG. 4 shows an exploded view of the interlocking system (300) to which modules (100) of the present invention have been attached.

FIG. 5 shows retention clips associated with interlocking system 300.

FIG. 6 shows a typical way in which retention clips are installed.

FIG. 7 shows various module (100) interlocking features.

FIG. 8 shows a module interlock system where two modules (100) are stacked, one on top of the other.

FIG. 9 shows a module interlock system where two modules (100) are connected side-to-side to one another.

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to a battery module, related devices and methods. More particularly, the present invention relates to a battery module with an improved mechanism of electrically connecting modules to form one or more battery packs and devices and methods that relate to the improved mechanism.

Modules and other devices according to the present invention are discussed in terms of the FIGURES below.

FIG. 1 shows an exploded view of a battery module (100) according to the present invention. As shown, the module includes battery module cases (101 and 102) and a battery module cover that come together through the application of fasteners (109 and 110) to form the outside casing of battery module 100. Battery module cases 101 and 102 are connected to form a bottom housing. Alternatively, the bottom housing may be molded such that it is a single piece of material, or such that it consists of four pieces of molded materials that are subsequently interconnected.

Battery module cover 103 includes a battery electronic cell control (111), as well as mechanisms for fasteners 109 and 110 to fasten it to the bottom housing. As shown, the bottom housing, which is constructed from battery module cases 101 and 102, has a set of outside features, including internal buss bar and power pin 104, internal buss bar and power sleeve 105, and cooling plates or heat sinks (108).

Internal buss bar and power pin 104 is designed such that it can insert into the internal buss bar and power sleeve from a different module. As shown, internal buss bar and power pin 104 makes electrical contact with the different module through insertion of the cylindrical pin into a cylindrical sleeve. Power pin 104 and power sleeve 105, however, can be made of any suitable shape other than cylindrical. Non-limiting examples of such shapes include lengths of conductive materials that are triangular, square, rectangular, pentagonal, hexagonal, heptagonal, octagonal or elliptical when viewed from an end.

Cooling plates or heat sinks 108 serve to dissipate heat generated by the operation of battery cells within module 100. Alternatively, heat sink 108 can be any suitable cooling system, including a water cooling system.

Internal buss bar and power sleeve 105 is designed such that it can receive an internal buss bar and power pin from a different module. Power sleeve 105, as shown, makes electrical contact with another module through insertion of the cylindrical power pin from the other module into the cylindrical power sleeve 105. As noted above, power sleeve 105 can be of any suitable shape other than cylindrical.

Optional lift handles are located on the outside of module 100, such that they can facilitate lifting, transporting and placing of module 100. As shown, the lift handles are roughly rectangular and are placed approximately mid-way on the surface of battery module cases 101 and 102. The lift handles may be placed, however, at any suitable point on module 100 and may be of any suitable shape.

As shown, the bottom housing, constructed from battery module cases 101 and 102, contains various features, including: one or more battery cells (106) and battery cell connection points (107).

The circuitry of the battery electronic cell control 111 may be of any suitable type. Nonlimiting examples of such circuitry are described in U.S. application Ser. No. 11/909,972, which published Oct. 16, 2008. and which is assigned to Energy Control Systems Engineering. This patent application is incorporated-by-reference into this document for all purposes.

Although cell connection points 107 are shown as being sonically welded together, any suitable method of joining cells together such that they can be contained within bottom housing may be used. Cells 106 are shown as being prismatic, but any suitable type of battery cell can be placed within the module of the present invention. Furthermore, any suitable chemistry can be used for cells 106 or those of other configurations. Nonlimiting examples of battery chemistries that can be included in cells are: lithium titanate; lithium iron phosphate; lithium iron magnesium phosphate; lithium polymer; and, lithium nickel oxide.

FIG. 2 shows an assembled view of the battery module (100) according to the present invention. As shown, battery module cover 103 has been fastened to battery module cases 101 and 102 through the securing of fasteners 109 and 110.

The modules according to the present invention are typically used to construct large format battery packs. In certain cases, the modules further include one or more clips or other locking mechanisms that fit into a track installed either on or within a substrate on which the battery pack is constructed. This arrangement serves to both increase the ease/efficiency of pack construction and to increase the mechanical stability (e.g., to shock and vibration) of the pack.

FIG. 3 shows a view of an interlocking system (300) to which modules (100) of the present invention have been attached. The following elements are shown in FIG. 3: module interlock assembly (300); track base (301); battery module (100); locking retention clip (302); and, locking retention clip (303).

A purpose of interlocking system 300 is to have a system that allows battery modules to be quickly assembled in large numbers of different layouts. Using a “family of parts” concept, battery modules (100) interlock with each other laying on their side (shown in FIG. 3) or standing upright. The battery modules interlock with base track (301) and locking retention clips 302 and 303 are used to lock them into position.

Base track 301 interconnects such that a track of any length can be created. Assembly requires no tools, which increases the safety of installation; modules 100 only assemble one way to prevent reverse polarization. Battery modules 100 will assemble to each other and to the base. Where desired, modules housing battery cells of different chemistry types can be of different sizes or configurations such that they cannot be inter-mixed on interlocking system 300.

FIG. 4 shows an exploded view of the interlocking system (300) to which modules (100) of the present invention have been attached. FIG. 5 shows retention clips associated with interlocking system 300. FIG. 6 shows a typical way in which retention clips are installed. FIG. 7 shows various module (100) interlocking features. FIG. 8 shows a module interlock system where two modules (100) are stacked, one on top of the other. FIG. 9 shows a module interlock system where two modules (100) are connected side-to-side to one another.

The battery modules of the present invention enable various actions, functions and efficiencies not achievable through the use of prior art modules. These enabled actions, etc. are shown most clearly in relation to safety, ease of large format pack assembly and proficiency relative to meeting certain testing standards (e.g., UN testing requirements for lithium ion batteries).

When the modules of the present invention are assembled into large format packs, the environmental health and safety risk associated with pack assembly is substantially reduced as compared to assembly using prior art modules. This is shown in terms of reduced accidental discharge profiles. Assembly using the modules described herein reduces the accidental discharge profile by at least 1% over that of any prior art module. In certain cases the accidental discharge profile is reduced by at least 2.5%, 5.0%, 7.5% or 10.0% over that of any prior art module. In still other cases, the accidental discharge profile is reduced by at least 15%, 20%, 25%, 30% or 35% over that of any prior art module.

The accidental discharge profile is measured in the following way;

• • the state-of-charge of one thousand (1000) different modules having battery cells of a particular chemistry (e.g., lithium titanate anode or lithium iron phosphate cathode) and particular configuration (e.g., prismatic) is determined (i.e., “SOC1”);
  • each of the modules is, in turn, connected to two (2) different modules, one at the positive terminal and the other at the negative;
  • each module must be connected to the two (2) different modules in less than 15 seconds;
  • each module is then disconnected, and the state-of-charge is again measured and recorded (i.e., “SOC2”);
  • accidental discharge is determined by the equation SOC2/SOC1.

When the modules of the present invention are assembled into large format packs, the efficiency of pack construction increases dramatically. This is shown in terms of reduced man hours needed to construct the pack. Construction using the modules described herein reduces the man hours needed to construct a pack by at least 2.5% over than of any prior art module. In certain cases, the number of man hours needed to construct a particular pack is reduced by at least 5.0%, 7.5%, 10.0% or 12.5%. In still other cases, the number of man hours is reduced by at least 15%, 20%, 25%, 30% or 35%. In certain cases, the number of man hours is reduced by at least 50%, 75% or 100%.

The number of man hours needed to put a pack together is measured in the following way:

• • a pack configuration containing at least twenty (20) modules in series is selected;
  • a time zero (i.e., “T0) a single person using only hand tools (e.g., socket wrench, screw driver, etc.) begins to construct the selected pack configuration using a specific module type;
  • when the last module—i.e., the 20^th—is connected, the time is recorded as time one (i.e., “T1”) is recorded in seconds;
  • the twenty (20) module pack configuration construction according to steps above is repeated at least five (5) times;
  • the number of man hours needed to put the pack together is calculated according to the equation (T1−T0)/3600.

When the modules of the present invention are assembled into large format packs, the proficiency by which the packs can pass UN testing protocols related to lithium ion batteries increases drastically. This is shown in terms of the increased percentage of packs that pass the vibration and shock testing requirements of the UN 38.3 lithium ion battery test. Testing using packs constructed using modules of the present invention increase the percentage of packs that pass the test by at least 2.5% over that of any prior art module. In certain cases, the percentage of packs passing the test is increased by at least 5.0%, 7.5%, 10.0% or 12.5%. In still other cases, the percentage is increased by at least 15%, 20%, 25%, 30% or 35%.

The percentage of packs passing the UN 38.3 test is measured in the following way:

• • a pack configuration containing at least twenty (20) modules connected in series is selected;
  • the selected pack configuration is constructed on a platform or substrate suitable for UN 38.3 testing, where the individual modules are not secured to the platform/substrate using bolts, welds or any other mechanical method;
  • the constructed pack is subjected to the UN 38.3 test at least twenty (20) times;
  • the percentage packs passing the UN 38.3 test is calculated according to the equation (number packs passed)/(number packs tested).

The various efficiencies and safety enhancements provided by the modules of the present invention significantly reduce the cost of constructing energy storage devices, which are oftentimes large format batteries/battery packs. This is especially true of energy storage devices that are connected directly or indirectly to the electrical grid. These devices may be connected to the grid for a wide variety of reasons, including performance of frequency regulation and/or peak shaving functions.

When the modules of the present invention are assembled into large format packs that are connected to the electrical grid, the cost of constructing the energy storage device containing the large format pack(s) is significantly reduced. In certain cases, the cost of constructing the energy storage device is reduced by at least 1.0%. In other cases, the cost is reduced by at least 2.5%, 5.0%, 7.5% or 10%. In still other cases, the cost is reduced by at least 15%, 20%, 25%, 30% or 35%.

The cost reduction of constructing an energy storage device is measured in the following way:

• • an energy storage device is designed, where the energy storage device includes at least twenty (20) modules connected in series, and where the device further includes a platform on which the device is constructed, and where the device further includes a variety of elements necessary to connect the large format pack (i.e., at least twenty (20) modules connected in series) to the electrical grid;
  • the cost of constructing the energy storage device is calculated using the modules of the present invention, where the cost includes the price of the various elements (e.g., modules) and the cost of constructing the device, including the cost of connecting the device to the grid (i.e., “COST1”);
  • the same cost is calculated using prior art modules (i.e., “COST2”);
  • the percentage of cost reduction is calculated using the equation [[100]−[(COST1/COST2)×100]%.

Claims

1. A battery module, wherein the module comprises: a battery module cover that connects to one or more battery module cases to form a housing; a first internal buss bar and power pin connected to a proximal end of the housing, wherein the first internal buss bar and power pin is shaped such that it can insert into a first internal buss bar and power sleeve from a second module; a second internal buss bar and power sleeve connected to a distal end of the housing, wherein the second internal buss bar and power sleeve is shaped such that it can receive a second internal buss bar and power pin from a third module; and, at least one electrochemical cell connected to the inside surface of at least one battery module case.

2. The battery module according to claim 1, wherein the end of the first internal buss bar and power pin is cylindrically shaped.

3. The battery module according to claim 2, wherein the electrochemical cell is a prismatic cell.

4. The battery module according to claim 3, wherein the outside surface of the housing comprises an element for cooling the module.

5. The battery module according to claim 4, wherein the battery module cover comprises at least one battery electronic cell control.

6. The battery module according to claim 5, wherein the prismatic cell is based on one of the following chemistries: lithium titanate chemistry; lithium iron phosphate chemistry; lithium nickel oxide chemistry; lithium manganese chemistry; lithium polymer chemistry; or lithium cobalt chemistry.

7. The battery module according to claim 6, wherein the module comprises a locking mechanism that is able to lock the module into a track.

8. The battery module according to claim 7, wherein there are more than one prismatic electrochemical cells connected to the inside surface of the housing, and the cells are connected to one another through their tabs.

9. The battery module according to claim 8, wherein the cells are connected through welding.

10. The battery module according to claim 8, wherein the element for cooling the module is a heat sink.

11. The battery module according to claim 10, wherein the element for cooling the water module is a water-based cooling system.

12. The battery module according to claim 10, wherein the module comprises at least one lift handle.

13. A large format battery pack, wherein the battery pack comprises at least two modules that are electrically connected to one another, and there is sufficient space between the modules to allow air flow when they are connected to one another, and wherein the modules each comprise: a battery module cover that connects to one or more battery module cases to form a housing; a first internal buss bar and power pin connected to a proximal end of the housing, wherein the first internal buss bar and power pin is shaped such that it can insert into a first internal buss bar and power sleeve from a second module; a second internal buss bar and power sleeve connected to a distal end of the housing, wherein the second internal buss bar and power sleeve is shaped such that it can receive a second internal buss bar and power pin from a third module; and, at least one electrochemical cell connected to the inside surface of at least one battery module case.

14. The large format battery pack according to claim 13, wherein the end of the first internal buss bar and power pin is cylindrically shaped, and wherein the electrochemical cell is a prismatic cell, and wherein the outside surface of the housing comprises an element for cooling the module.

15. The large format battery pack according to claim 14, wherein the battery module cover comprises at least one battery electronic cell control, and wherein the prismatic cell is based on lithium titanate chemistry, lithium iron phosphate chemistry, lithium nickel oxide chemistry, lithium manganese chemistry, lithium polymer chemistry, or lithium cobalt chemistry, and wherein the module comprises a locking mechanism that is able to lock the module into a track, and wherein there are more than one prismatic electrochemical cells connected to the inside surface of the housing, and wherein the cells are connected to one another through their tabs.

16. The large format battery pack according to claim 15, wherein the module comprises at least one lift handle, and wherein the cells are connected through ultrasonic welding, and wherein the housing comprises ribs that increase its mechanical strength.

17. A method of reducing the accidental discharge profile associated with assembling a large format battery pack by at least 1 percent, wherein the method comprises the steps of assembling the pack with at least twenty modules, and wherein each of the modules comprise: a battery module cover that connects to one or more battery module cases to form a housing; a first internal buss bar and power pin connected to a proximal end of the housing, wherein the first internal buss bar and power pin is shaped such that it can insert into a first internal buss bar and power sleeve from a second module; a second internal buss bar and power sleeve connected to a distal end of the housing, wherein the second internal buss bar and power sleeve is shaped such that it can receive a second internal buss bar and power pin from a third module; and, at least one electrochemical cell connected to the inside surface of at least one battery module case.

18. The method according to claim 17, wherein the end of the first internal buss bar and power pin is cylindrically shaped, and wherein the electrochemical cell is a prismatic cell, and wherein the outside surface of the housing comprises an element for cooling the module.

19. The method according to claim 18, wherein the battery module cover comprises at least one battery electronic cell control, and wherein the prismatic cell is based on lithium titanate chemistry, lithium iron phosphate chemistry, lithium nickel oxide chemistry, lithium manganese chemistry, lithium polymer chemistry, or lithium cobalt chemistry, and wherein the module comprises a locking mechanism that is able to lock the module into a track, and wherein there are more than one prismatic electrochemical cells connected to the inside surface of the housing, and wherein the cells are connected to one another through their tabs.

20. The method according to claim 19, wherein the module comprises at least one lift handle, and wherein the cells are connected through ultrasonic welding, and wherein the housing comprises ribs that increase its mechanical strength.