Energy storage device and method for operating it

• US 10,008,865 B2
• Filed: 10/11/2013
• Issued: 06/26/2018
• Est. Priority Date: 10/19/2012
• Status: Active Grant

• Current Assignee: H-Tech Ag
• Original Assignee: H-Tech Ag
• Inventors: Hempel, Jrg
• Primary Examiner(s): GRANT, ROBERT J
• Application Number:
  US14/436,778
• Publication Number:
  US 20150333543A1
• Time in Patent Office: 1,719 Days
• Field of Search: 320121
• CPC Class Codes: B60L 2240/12 Speed
• CPC Class Codes: B60L 2240/545 Temperature
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 2240/549 Current
• CPC Class Codes: B60L 50/52 characterised by DC-motors
• CPC Class Codes: B60L 58/13 Maintaining the SoC within a determined range
• CPC Class Codes: B60L 58/19 Switching between serial connection and parallel connection of battery modules
• CPC Class Codes: B60L 58/22 Balancing the charge of battery modules
• CPC Class Codes: H01M 10/441 for several batteries or cells simultaneously or sequentially
• 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: H02J 7/0014 Circuits for equalisation of charge between batteries
• CPC Class Codes: H02J 7/0018 using separate charge circuits
• CPC Class Codes: H02J 7/00711 with introduction of pulses during the charging process
• CPC Class Codes: H02J 7/14 for charging batteries from dynamo-electric generators driven at varying speed, e.g. on vehicle
• CPC Class Codes: H02J 7/342 The other DC source being a battery actively interacting with the first one, i.e. battery to battery charging with circuits for polarity protection H02J7/0034
• 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 energy storage device and a method for the operation of an energy storage device. In order to state an energy storage arrangement and a method for the operation of the latter, which in their characteristics are adapted to complex requirements and show both high-current and high-energy characteristics, an energy storage arrangement is stated, including: at least one high-current cell and at least one high-energy cell, with the at least one high-energy cell and the at least one high-current cell being connected in parallel, with the cells being charged and/or discharged with a current pulse and in the inter-pulse periods a charge balancing taking place between the cells.

Claims

1. Energy storage arrangement, comprising:

at least one high-current rechargeable battery cell and at least one high-energy rechargeable battery cell, with the at least one high-energy rechargeable battery cell and the at least one high-current rechargeable battery cell being connected in parallel,

with the rechargeable battery cells being charged and/or discharged with current pulses,

wherein inter-pulse periods are arranged between said current pulses, and

wherein said at least one high-energy rechargeable battery cell is configured to recharge said at least one high-current rechargeable battery cell during rest periods after a load requirement needing a high current,

a control unit to control the pulse lengths and/or pulse amplitudes of the current pulse for charging and/or discharging of the rechargeable battery cells,

wherein, during charging, by using adaptive current pulses, charge balancing takes place systematically between the two rechargeable cell types during the inter-pulse periods as the high-energy rechargeable battery cell works as a load for the high-current rechargeable battery cell during the inter-pulse periods,

wherein the control unit being connected to a first switch unit, a second switch unit, a third switch unit and/or a fourth switch unit that couples the at least one high current rechargeable battery cell and the at least one high-energy rechargeable battery cell, in order to supply a switch pulse to the latter to open and/or close the respective switch unit, with the switch unit continuing to be connected to the current, voltage and/or temperature measuring devices in order to receive measuring signals from the latter,

wherein by means of closing of the fourth switch unit during the inter-pulse periods the at least one high-current rechargeable battery cell being discharged by a load pulse.

2. Energy storage arrangement according to claim 1, wherein the first switch unit being arranged upstream of at least the high-energy rechargeable battery cell, and the second switch unit being arranged upstream of at least the high-current rechargeable battery cell.

3. Energy storage unit according to claim 2, wherein the first switch unit is adapted to control the discharging and/or charging process of the high-energy rechargeable battery cell and/or of the high-current rechargeable battery cell.

4. Energy storage arrangement according to claim 2, wherein the control unit is provided for pulsing of the first switch unit for controlling the pulse lengths and/or inter-pulse periods of the current pulse during charging and/or discharging of the rechargeable battery cells.

5. Energy storage arrangement according to claim 1, wherein the first switch unit is adapted to interrupt the supply of current into and/or the current consumption from the associated rechargeable battery cell for a predetermined time and preferably cause a periodic pulsing of the current supply and/or of the current consumption.

6. Energy storage arrangement according to claim 1, further comprising at least one current measuring device and/or voltage measuring device and/or temperature measuring device wherein the measured values are used for the controlling of the charging and/or discharging process.

7. Energy storage arrangement according to claim 1, wherein the third switch unit being arranged upstream of the connection in parallel of the at least one high-current battery cell and the at least one high-energy rechargeable battery cell and serving the purpose of current limiting for both rechargeable battery cells.

8. Energy storage arrangement according to claim 2, wherein the pulsing of the first switch unit for the at least one high-current rechargeable battery cell being adapted to and coordinated with the pulsing of the second switch unit for the at least one high-energy rechargeable battery cell.

9. Energy storage arrangement according to claim 1, wherein the fourth switch unit that couples the at least one high current rechargeable battery cell and the at least one high-energy rechargeable battery cell is closed in order to make possible a flow of current from the high-current rechargeable battery cell into the high-energy rechargeable battery cell or vice versa and/or the fourth switch unit being pulsed in order to achieve current limiting.

10. Energy storage arrangement according to claim 1, wherein during a pulsed discharging process in the inter-pulse periods or during stationary phases offload with a closed connection between the at least one high-energy rechargeable battery cell and the at least one high-current rechargeable battery cell a current flowing from the at least one high-energy rechargeable battery cell into the at least one high-current rechargeable battery cell, in order to recharge the latter.

11. Energy storage arrangement according to claim 2, wherein the current from the energy storage arrangement being able to be limited during a discharging process by means of one of the switch units.

12. Energy storage arrangement according to claim 1, wherein the current pulse switching back and forth between a low level of zero amps and a fixed positive current value.

13. Energy storage arrangement according to claim 2, wherein at least one of the switch units being controlled in such a way that upon reaching the end of discharge voltage of one of the two types of rechargeable battery cells, current limiting is carried out by means of pulsing of one of the switches.

14. Energy storage arrangement according to claim 1, wherein the length of the current pulses and/or of the inter-pulse periods being set as a function of the measured state of the two rechargeable battery cell types.

15. Method for the charging or discharging of an energy storage arrangement comprising a connection in parallel of at least one high-current rechargeable battery cell and at least one high-energy rechargeable battery cell,

wherein said at least one high-energy rechargeable battery cell is configured to recharge said at least one high-current rechargeable battery cell during rest periods after a load requirement needing a high current,

the method comprising the steps:

charging or discharging of at least one high-current rechargeable battery cell and at least one high-energy rechargeable battery cell with current pulses, wherein inter-pulse periods are arranged between said current pulses,

controlling the pulse lengths and/or pulse amplitudes of the current pulse for charging and/or discharging of the rechargeable battery cells by use of a control unit,

wherein, during charging, by using adaptive current pulses, charge balancing takes place systematically between the two rechargeable cell types during the inter-pulse periods as the high-energy rechargeable battery cell works as a load for the high-current rechargeable battery cell during the inter-pulse periods,

wherein the at least one high current rechargeable battery cell and the at least one high-energy rechargeable battery cell are coupled via a switch unit,

wherein by means of closing of the switch unit that couples the at least one high current rechargeable battery cell and the at least one high-energy rechargeable battery cell during the inter-pulse periods the at least one high-current rechargeable battery cell being discharged by a load pulse.

16. Method according to claim 15, wherein upon reaching of the end of charge voltage of the high-current rechargeable battery cells or of the high-energy rechargeable battery cells switching-off of the supply of the current pulse to the appropriate rechargeable battery cell and further charging of the other one of the two rechargeable battery cells up to the reaching of the end of charge voltage of the other one of the two rechargeable battery cells, wherein during an inter-pulse period between the current pulses the two high-current rechargeable battery cells and high-energy rechargeable battery cells are connected to each other to allow a flow of current from the high-current rechargeable battery cells to the high-energy rechargeable battery cells.

17. Method according to claim 15, further comprising the steps:

monitoring of end of discharge voltage, current flow and/or temperature of the at least one high-current rechargeable battery cell and/or at least one high-energy rechargeable battery cell;

upon exceeding of a limit value of the end of discharge voltage, current flow or temperature limiting of the discharging current from the high-energy rechargeable battery cell or from the high-current rechargeable battery cell by pulsing of the switch unit, wherein due to the closing of the switch unit between the two high-current rechargeable battery cells and high-energy rechargeable battery cells connected in parallel, charge balancing taking place between the high-current rechargeable battery cells and the high-energy rechargeable battery cells.