EP3894271A1

EP3894271A1 - Energy store for an electrically drivable means of transportation

Info

Publication number: EP3894271A1
Application number: EP19832605.0A
Authority: EP
Inventors: Johannes Grabowski; Joachim Joos; Walter Von Emden; Andreas Keller
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2018-12-14
Filing date: 2019-12-16
Publication date: 2021-10-20
Also published as: CN113195301A; US20220029211A1; DE102018221836A1; WO2020120792A1

Abstract

The invention relates to an energy store (1) comprising a housing (2), a first plurality of storage cells (3a, 3b), a second plurality of storage cells (4a, 4b), a first electric connection assembly (8), a second electric connection assembly (9), and a switching device (10). The switching device (10) is designed to connect the first plurality of storage cells (3a, 3b) to the first electric connection assembly (8), to connect the second plurality of storage cells (4a, 4b) to the second electric connection assembly (9), and/or to connect the first plurality of storage cells (3a, 2b) to the second plurality of storage cells (4a, 4b).

Description

description

title

Energy storage for an electrically drivable form of transportation

State of the art

The present invention relates to an energy store, in particular for an electrically drivable means of transportation. In particular, the present invention relates to a flexible and energy-efficient mode of operation of an energy store.

Current electromobility solutions include a passive one

interconnected battery pack active components that include an inverter, DC-DC converter, additional 12 V / 48 V batteries, power conversion units

(Energy converter, PCU), soft start contactors and charge controller. This is a sometimes complex and costly system. The passive interconnection of the individual battery cells (e.g. with a single source voltage of 3.7 V) and the production-related differences in internal resistance and capacity also result in significantly different loads on the individual cells and possible further drifting apart during operation. The capacity of the entire battery pack is thus determined based on the performance of the cells with the poorest state of health or the lowest state of charge, which necessitates a reserve that limits the usable capacity to 60% to 80% of the nominal capacity in order to avoid the harmful deep discharge of the cell to avoid the lowest capacity. The present invention pursues the task of shifting the functionality into the individual cell, so that each individual cell can also be used optimally or optimally for an external power request (ferry operation, work operation or the like) or a power supply (charging operation, recuperation operation or the like ...) react and contribute if necessary.

Disclosure of the invention To this end, the present invention proposes a system which, for example, has an ASIC, sensors and switches, which can be implemented on each individual battery cell. In other words, intelligent battery cells can be used as the basic unit for the present invention. The ASIC of the respective cell or system contains one

Memory / data memory that has a unique identification, so that each battery cell is uniquely assigned, and sensors, e.g. Temperature, currents, number of charge / discharge cycles, cell voltage and possibly occurring fault cells, e.g. Detect and save deep discharge, high temperatures, etc. A bus system can enable communication from every single cell with the consumers or the charging station. Active switches (e.g. MOSFETs) on each individual cell enable a wide variety of cells to be connected in series and / or in parallel and appropriate voltages to be applied to various external consumers. An algorithm on each ASIC of a respective system of a respective cell can enable the respective cell to evaluate how the individual cell can contribute to the performance requirement or whether this is not sensible in the present case.

In other words, the above The object is achieved by an energy store which has a housing, a first plurality of storage cells, a second plurality of storage cells, a first electrical connection arrangement, a second electrical connection arrangement and a switching device. The housing can be made of plastic, for example

To ensure acid resistance and to be insensitive to corrosion. The memory cells of the first plurality of memory cells can

for example as power cells, energy cells, and alternatively or additionally as a mixture of the aforementioned cells. For this purpose, individual or all of the first plurality of memory cells can also be designed as super-caps. The same applies to the second plurality of memory cells. In particular, the first plurality of memory cells can have a different nature of memory cells than the second plurality of memory cells. In particular, all of the memory cells of the first plurality of memory cells are of a different nature than the second plurality of memory cells (and / or vice versa). The first electrical connection arrangement and the second electrical connection arrangement can be provided to supply external consumers with electrical energy from the energy stores or from the storage cells. About the first electrical connection arrangement, an electrical consumer can in particular be supplied with electrical energy independently of the second electrical connection arrangement. In particular, the first electrical connection arrangement and the second electrical connection arrangement

set up to output different electrical voltages by being electrically connected to a different plurality of memory cells. For this purpose, the first plurality of memory cells with the first electrical

Connection arrangement can be connected while the second variety

Memory cells is connected to the second electrical connection arrangement. The switching device is also set up to optionally electrically connect the first plurality of memory cells to the second plurality of memory cells. In this way, the energy, the voltage and / or the current strength of the storage cells can be selected via the first electrical one

Connection arrangement, the second electrical connection arrangement and / or both the first and the second electrical connection arrangement are emitted from the energy store. The switching device can be set up as a function of an operating state of a machine or machine to be supplied with electrical energy by the energy store

to operate appropriate means of transportation. In this way, the storage cells of the energy store can be different

Terminal voltage characteristics are energetically supplied, which improves the use of an energy store according to the invention compared to arrangements known in the prior art.

The subclaims show preferred developments of the invention.

The first connection arrangement and / or the second connection arrangement can each have at least two electrical contacts, via which electrical energy of the memory cells can be transmitted. Depending on the intended use or working mode of the energy store, it is therefore possible to transmit electrical energy from the first plurality of storage cells to the second plurality of storage cells via the respective electrical contacts and / or to indicate electrical energy to consumers arranged outside the housing. The electrical contacts are acted upon electrically by means of the switching device of the energy store. In particular, there is also an analysis of the need to activate the switching device within the energy store according to the invention. This increases flexibility in use of the energy store according to the invention and eliminates the need for a higher-level logic / control unit and the one connected to it

Wiring effort.

When “energy cells” is referred to in the context of the present disclosure, this refers to the property of the plurality of storage cells that they are essentially designed to provide a large amount of energy. In other words, the storage cells referred to as energy cells have the highest possible energy capacity. In contrast to this, the term "power cells" refers to the large number of memory cells that are in the

Are essentially set up to deliver high electrical outputs. The maximum power output of the power cells can be significantly higher than that of the aforementioned energy cells, in particular in comparison to their energetic capacity. Through the use of memory cells of different characteristics, an inventive method can be used

Energy storage particularly suitable and flexible to respond to requests for the provision of electrical energy.

The switching device can, for example, be set up to electrically decouple the first plurality of memory cells and the second plurality of memory cells from one another in response to an energy supply request from a first (external) consumer and to electrically connect the first plurality of memory cells or the second plurality of memory cells to the first connection arrangement. The first consumer is thus electrically connected to the energy store and the memory cells of the first plurality of memory cells contained therein via the first connection arrangement. At the same time, the first consumer can be electrically decoupled from the second plurality of memory cells, so that the second plurality of memory cells are not loaded by the first consumer and are available without restriction for supplying other external consumers. In this way, no compromises have to be made in the supply of electrical consumers, so that, for example, voltage-sensitive electrical consumers can be supplied by a large number of storage cells which are not supplied by another (e.g.

performance-intensive) consumers. The electrical characteristics of the first consumer can thus be satisfied as best as possible by the first plurality of memory cells. The switching device of the energy store according to the invention can be set up to electrically connect the first consumer to the first plurality of memory cells or the second plurality of memory cells depending on its nominal voltage. In other words, either the actual power consumption of the first electrical consumer can decide whether the switching device considers it helpful to electrically connect the first consumer to the second plurality of memory cells instead of the first plurality of memory cells, or both to the first plurality instead

To electrically connect memory cells as well as to the second plurality of memory cells. Alternatively, with knowledge of the consumer to be supplied with electricity by the energy store and its parameters, the switching device can be activated even before electrical energy is drawn from the energy store

Make a decision as to whether the first consumer can be better supplied with electrical energy via the first plurality of storage cells and / or via the second plurality of storage cells. This can also be done taking into account other consumers that are currently being supplied with energy from the electrical energy store or are to be supplied with energy from the electrical energy store in the future. In this way, the electrical consumers to be supplied can be used as best as possible

lowest possible conversion losses due to the in the energy storage

contained storage cells are supplied with electrical energy.

According to the invention, each memory cell can have an evaluation unit, which is set up in response to a request and depending on its own state of health and / or state of charge to decide whether it should connect to the first electrical connection arrangement and / or to the second electrical connection arrangement. The evaluation unit can be understood as “intelligence” of the respective memory cell, so that there are a large number of intelligent memory cells within the energy store according to the invention. These can be one

Form "swarm intelligence". The need for signaling within an energy store designed according to the invention can be reduced in this way. In particular, data communication lines between the memory cells can be dispensed with in that each memory cell has a respective evaluation unit. The evaluation unit can

Have communication unit or be connected to such information technology. In particular, the communication unit can accordingly the evaluation unit can be contained in each memory cell. In addition, a respective sensor unit within the memory cell can be linked to the evaluation unit in terms of information technology. In this way, the storage cell can monitor its own performance, its own state of charge and its own state of health in the best possible way and, depending on the aforementioned variables, independently decide whether it participates in the energy supply of external consumption or not. This modularization also makes it possible to flexibly maintain an energy store according to the invention, since only electrical connections have to be connected between the old storage cells and an exchanged / newly added storage cell, while communication with a higher-level evaluation unit which may be further away is eliminated.

If the memory cells of the energy store according to the invention have a respective evaluation unit (and optionally a respective communication unit), the evaluation unit can be set up in response to an electrical connection of another memory cell to the first electrical connection arrangement, to decide whether it connects to the first electrical connection arrangement or Not. In other words, it can

Memory cell determine the switching process (for example, by its own electrical sensor system), and in response to it decide again whether or not it makes sense to participate in the energetic supply of the electrical consumer. In other words, the memory cell is able, by means of its evaluation unit, in combination with the invention

Energy storage to make a decentralized decision as to whether it is electrically connected to a further storage cell and / or an external electrical consumer via the switching device of the energy storage.

The sensor system mentioned above, optionally provided in each memory cell or at least in individual memory cells, can include a temperature sensor and alternatively or additionally a voltage sensor (in particular an undervoltage sensor) and alternatively or additionally a sensor / counter for determining a number of cycles of the memory cell and alternatively or additionally a current sensor Have measurement of the cell currents of the memory cell. As an alternative or in addition, the sensor system can carry out a cell spectroscopy of the memory cell in that it electrically operates the memory cell in a predefined manner loaded and the response of the memory cell depending on the load is determined using a predefined reference. A conclusion on the state of health and / or the cell chemistry can be drawn from the result of the determination.

The energy store according to the invention can, for example, be provided in an electrically drivable means of transportation. As an alternative or in addition, the electrical energy store can be provided in a work machine and / or to support an island network. The above Features,

Combinations of features and advantages arise for these and others

Purposes in a corresponding manner, so that to avoid

Repetitions in this regard, reference is made to the above statements.

Brief description of the drawing

Exemplary embodiments of the invention are described in detail below with reference to the accompanying drawing. In the drawing is:

Figure 1 is a schematic representation of an embodiment of an energy storage device according to the invention, and

Figure 2 is a schematic representation in more detail

Embodiments for switching devices according to the invention in the form of switching matrices.

Embodiments of the invention

Figure 1 shows an embodiment of an inventive

Energy storage 1, on the housing 2 two electrical

Connection arrangements 8, 9 are connected to a first electrical consumer 11 and a second electrical consumer 12. Optional

Communication bus lines 15 connect the consumers 11, 12 to cell modules 20a, 20b, 20c, 20d arranged inside the housing 2. The cell modules 20a are designed as power cells. Their memory cells 3a, 3b are capable of delivering comparatively high electrical outputs compared to their storage capacity. Energy cells 4a, 4b of the cell modules 20b, on the other hand, are capable of one compared to the maximum power that they can deliver to store a large amount of energy. Super-caps 5a, 5b of the cell modules 20c are set up to deliver extremely high power at short notice with particularly low electrical losses and lower capacity. Also are

Cell modules 20d with shunts 6a, 6b are provided, which offer a flexible possibility for converting (“annihilating”) electrical energy within the

represent energy storage 1 according to the invention. The switching devices 13 of the cell modules 20a to 20d enable the ASICs 7 as evaluation units to electrically connect the power cells 3a, 3b, the energy cells 4a, 4b, the super-caps 5a, 5b and the shunts 6a, 6b to a central switching device 10. In this way, the switching device 10, on which in

2 in detail, flexibly use the energies or shunts of the cell modules 20a to 20d to use the electrical

Connection arrangements 8, 9 to supply the external consumers 11, 12 with electrical energy. Sensors 14 within the cell modules 20a to 20d enable the voltages or temperatures and the flowing currents within the cell modules 20a to 20d to be monitored. The memory cells 3a, 3b, 4a, 4b, 5a, 5b can also use the respective sensors 14 to determine the undervoltage, number of cycles and cell chemistry (e.g. using a

Cell spectroscopy). The respective ASIC 7 of the cell modules 20a to 20d can receive or communicate information about the current or the intended operating state of the external consumers 11, 12 via the communication bus 15. Information about the states of the

Cell modules 20a to 20d and the previous communication can be stored by the ASIC 7 of the respective cell module 20a to 20d. In addition, the ASIC 7 can store information on cell profiles and behavior models for the cell modules 20a to 20d.

Figure 2 shows a possible implementation of an inventive

Energy store 1, which according to FIG. 1 has a plurality of cell modules 20a and 20b and a switching device 10 shown in detail in the form of a switching matrix. The first plurality of memory cells within the cell modules 20a and 20b can be bridged via a respective switch S. The electrical contacts 8a, 8b and 9a, 9b of the electrical connection arrangements 8, 9 arranged on the outside of the housing (not shown) can be flexibly electrically connected to any number of cell modules 20a, 20b via the plurality of switches provided within the switching device 10, and thus flexibly with a suitable number of storage cells are supplied with energy. In other words, FIG. 2 shows a possible implementation of the dynamic interconnections of the battery cells on battery strings. Each cell controls the switches associated with it. A string denotes the switches shown one above the other within the switching device 10. The cells of the cell modules 20a, 20b can dynamically hook into them. If none of the cell modules 20a, 20b decides to latch electrically into the respective string, the short-circuit switch S automatically closes. The strings can generate different voltages with the different memory cells. A feedback via the common bus (see FIG. 1) enables the individual cell modules 20a, 20b to make the decision taking into account the decision of the other cells.

A decentralized regulation of the

Enables energy flows of an energy storage device in connection with its environment. In this way, the advantage of an optimal matching between energy provision (energy storage side) and energy consumers

(Consumer side) without large central switches, battery management system, etc. Every energy flow is switched dynamically and takes into account the current state of the battery cell and consumer. As a result, the lifespan of the energy store is increased and the efficiency of the overall system is optimized.

All of the cells can be operated at the optimum operating point thanks to the structure mentioned above. The cell stress can vary according to the current

Judge cell performance. In the overall system with active battery packs, central assemblies such as inverters, ECUs,

Battery management systems (BMS), DC-DC converters, etc. New systems and system configurations can be put together very easily.

In particular, new vehicle types and wiring system requirements can be met flexibly and at short notice. The system is highly flexible with e.g.

Capacity expansions, in the event of the loss of individual cells, in the event of maintenance, interception of errors, etc.

Furthermore, the failure of individual cells no longer leads to the failure of the

Overall system, since individual cells can be bridged. The thermal runaway of individual cells, for example in the event of mechanical damage, can be intercepted by other cells, shunts and consumers dynamically can be connected. Individual (weak) cells can be identified and replaced individually. The individual switches can ensure that the maintenance work is de-energized at any time. The charging energy can be optimally distributed to the cells: a few charged cells can absorb more energy, the total charge of the battery pack increases faster, which reduces charging times. The range can be increased by the efficient use of the stored energy at the optimum working point and the mix of energy, power and super-cap cells. The lower load for cyclized cells related to the critical cells due to the operation in the optimal operating point of each cell by deep discharge can be excluded. So that the life of the

Energy storage can be increased drastically.

Claims

Expectations

1. Energy storage device (1) comprising:

a housing (2),

a first plurality of memory cells (3a, 3b),

a second plurality of memory cells (4a, 4b),

a first electrical connection arrangement (8),

a second electrical connection arrangement (9) and

a switching device (10) which is set up

the first plurality of memory cells (3a, 3b) with the first electrical

To connect the connection arrangement (8),

to connect the second plurality of memory cells (4a, 4b) to the second electrical connection arrangement (9), and / or the first plurality of memory cells (3a, 3b) to the second plurality

Connect memory cells (4a, 4b).

2. Energy store (1) according to claim 1, wherein the first connection arrangement (8) and the second connection arrangement (9) each have at least two electrical contacts (8a, 8b, 9a, 9b), via which electrical energy of the storage cells (3a, 3b , 4a, 4b, 5a, 5b) can be transmitted.

3. Energy store (1) according to claim 1 or 2, wherein

the first electrical connection arrangement (8) and

the second electrical connection arrangement (9) on the outside of the housing

(2) are arranged.

4. Energy store (1) according to one of the preceding claims, wherein the first plurality of storage cells (3a, 3b) comprises a plurality of energy cells, in particular consists of energy cells, and / or

the second plurality of memory cells (4a, 4b) comprises a plurality of power cells, in particular consists of power cells.

5. Energy store (1) according to one of the preceding claims, wherein the switching device (10) is set up in response to a

Energy supply request from a first consumer (11)

electrically decouple the first plurality of memory cells (3a, 3b) and the second plurality of memory cells (4a, 4b) and the first plurality of memory cells (3a, 3b) or the second plurality of memory cells (4a, 4b) electrically with the first connection arrangement (8 ) connect to.

6. Energy store (1) according to one of the preceding claims, wherein the switching device (10) is set up in response to a

Energy supply request from a first consumer (11) and a second consumer (12)

electrically decouple the first plurality of memory cells (3a, 3b) and the second plurality of memory cells (4a, 4b) from each other, electrically connect the first plurality of memory cells (3a, 3b) to the first connection arrangement (8) and

to electrically connect the second plurality of memory cells (4a, 4b) to the second connection arrangement (9).

7. Energy store (1) according to one of the preceding claims 5 or 6, wherein the switching device (10) is set up, the first consumer (11) depending on its nominal voltage with the first plurality of memory cells (3a, 3b) or the second plurality of memory cells ( 4a, 4b) to be electrically connected.

8. Energy store (1) according to one of the preceding claims, wherein each memory cell (3a, 3b, 4a, 4b) has an evaluation unit (7) which is set up in response to a request and in

Dependence on one's own state of health and / or

Decide the state of charge whether they are with the first electrical connection arrangement (8) and / or with the second electrical

Connection arrangement (9) connects.

9. Energy store (1) according to one of the preceding claims, wherein each memory cell (3a, 3b, 4a, 4b) has an evaluation unit (7) which is set up in response to an electrical connection another memory cell (3a, 3b, 4a, 4b) for the first electrical connection arrangement (8) to decide whether it connects to the first electrical connection arrangement (8) or not.

10. Energy store (1) according to one of the preceding claims, wherein each memory cell (3a, 3b, 4a, 4b) has a sensor system (14) which is set up

a temperature and / or

an undervoltage and / or

- a number of cycles and / or

Measure cell currents of the memory cell (3a, 3b, 4a, 4b) and / or perform a cell spectroscopy of the memory cell (3a, 3b, 4a, 4b).