Switched passive architectures for batteries having two different chemistries

Patent metadata

Field	Value
Publication number	US-10062892-B2
Application number	US-201615389772-A
Country	US
Kind code	B2
Filing date	Dec 23, 2016
Priority date	Jul 31, 2013
Publication date	Aug 28, 2018
Grant date	Aug 28, 2018

Abstract

A 12 volt automotive battery system includes a first battery coupled to an electrical system, in which the first battery include a first battery chemistry, and a second battery coupled in parallel with the first battery and selectively coupled to the electrical system via a first switch, in which the second battery includes a second battery chemistry that has a higher coulombic efficiency than the first battery chemistry. The first switch couples the second battery to the electrical system during regenerative braking to enable the second battery to capture a majority of the power generated during regenerative braking. The 12 volt automotive battery system further includes a variable voltage alternator that outputs a first voltage during regenerative braking to charge the second battery and a second voltage otherwise, in which the first voltage is higher than the second voltage.

First claim

The invention claimed is:

1. A method for implementing a 12 volt automotive battery system, comprising:
electrically coupling a first battery to an electrical system, wherein the first battery comprises a first battery chemistry;
electrically coupling a second battery and a first switch in parallel with the first battery to enable the first switch to selectively couple the second battery to the electrical system, wherein:
the second battery comprises a second battery chemistry that has a higher coulombic efficiency than the first battery chemistry; and
electrically coupling the second battery and the first switch in parallel with the first battery comprises electrically coupling the first switch between the second battery and the electrical system to enable the first switch to:
electrically connect the second battery to the electrical system during regenerative braking to enable the second battery to capture a majority of electrical power generated during regenerative braking; and
electrically disconnect the second battery from the electrical system during a period when regenerative braking is not occurring; and

electrically coupling a variable voltage alternator that outputs a first voltage during regenerative braking to charge the second battery and outputs a second voltage otherwise to the first switch, wherein the first voltage is higher than the second voltage; and
communicatively coupling battery control unit to the first battery, the second battery, the first switch the electrical system, the variable voltage alternator, or any combination thereof to enable the battery control unit to maintain the first battery generally at a full state of charge before regenerative braking to enable the first battery to steer the electrical power generated during regenerative braking to the second battery using internal resistance of the first battery.

2. The method of claim 1 , wherein electrically coupling the first battery to the electrical system comprises:
electrically coupling a second switch between the first battery and the second battery, wherein first battery and the second switch are electrically coupled in parallel with the second battery and the first switch; and
electrically coupling the second switch to the variable voltage alternator to enable the second switch to electrically disconnect the first battery during regenerative braking when the first voltage output by the variable voltage alternator is higher than a maximum charging voltage of the first battery.

3. The method of claim 1 , wherein:
electrically coupling the first battery to the electrically system comprises:
electrically coupling the first battery between a positive terminal and a negative terminal of a battery module; and
electrically coupling the positive terminal and the negative terminal to the electrical system;

electrically coupling the second battery and the first switch in parallel with the first battery comprises:
electrically coupling the first switch between the second battery and the positive terminal; and
electrically coupling the second battery to the negative terminal.

4. The method of claim 3 , comprising forming a housing that around the first battery, the second battery, and the first switch, wherein the positive terminal and the negative terminal extend from the housing.

5. The method of claim 1 , wherein:
the first battery comprises a lead-acid battery cell; and
the second battery comprises a lithium-ion battery cell that has a higher charge acceptance rate than the lead-acid battery cell, wherein the lithium-ion battery cell comprises a lithium nickel manganese cobalt oxide battery cell, a lithium nickel cobalt aluminum oxide battery cell, a lithium nickel manganese cobalt oxide-lithium nickel cobalt aluminum oxide battery cell, a lithium-titanate/lithium nickel manganese cobalt oxide batter cell, a nickel-metal hydride battery cell, or a lithium iron phosphate battery cell.

6. A battery module, comprising:
a positive terminal and a negative terminal configured to electrically couple the battery module to an electrical system of an automotive vehicle;
a first plurality of battery cells electrically coupled between the positive terminal and the negative terminal, wherein each of the first plurality of battery cells comprises a first battery chemistry;
a second plurality of battery cells electrically coupled to the negative terminal, wherein each of the second plurality of battery cells comprises a second battery chemistry that has a higher charge acceptance rate than the first battery chemistry; and
a switching device electrically coupled between the second plurality of battery cells and the negative terminal, wherein the switching device is configured to:
close while the automotive vehicle performs regenerative braking to enable the second plurality of battery cells to capture a majority of electrical power generated by an electrical generator during regenerative braking; and
while the automotive vehicle is not performing regenerative braking:
close to enable the second plurality of battery cells to supply electrical power to the electrical system when a first open circuit voltage across the second plurality of battery cells is greater than a voltage threshold; and
open when the first open circuit voltage across the second plurality of battery cells is not greater than the voltage threshold.

7. The battery module of claim 6 , wherein:
the battery module comprises a 12 volt battery module; and
the first open circuit voltage across the second plurality of battery cells is between 7 volts and 18 volts.

8. The battery module of claim 6 , comprising a second switching device electrically coupled between the first plurality of battery cells and the positive terminal, wherein:
the positive terminal and the negative terminal are configured to electrically couple the battery module to the electrical generator;
the electrical generator is configured to convert mechanical energy of the automotive vehicle into the electrical power while the automotive vehicle performs regenerative braking; and
the second switching device is configured to open when voltage of electrical power output during regenerative braking is greater than a maximum charging voltage of the first plurality of battery cells.

9. The battery module of claim 8 , wherein:
the positive terminal and the negative terminal are configured to electrically couple the battery module to an ignition system, wherein the battery module is configured to supply electrical power to the ignition system to crank an internal combustion engine in the automotive vehicle; and
the second switching device is configured to open and the switching device is configured to close to enable the second plurality of battery cells to supply electrical power used to crank the internal combustion engine by itself.

10. The battery module of claim 6 , comprising a battery control unit communicatively coupled to the first switching device and a sensor, wherein the battery control unit is configured to:
instruct the switching device to switch from an open position to a closed position, to switch from the closed position to the open position, maintain the open position, maintain the closed position, or any combination thereof; and
determine the first open circuit voltage across the second plurality of battery cells based at least in part on sensor data received from the sensor.

11. The battery module of claim 10 , comprising a housing enclosing the first plurality of battery cells, the second plurality of battery cells, and the switching device, wherein the positive terminal and the negative terminal extend out from an external surface of the h

Assignees

• Johnson Controls Tech Co

Inventors

• Wyatt Perry M
• Le Daniel B
• Mascarenhas Ryan S
• Sisk Brian C

Classifications

• H01M10/06 Primary

  Lead-acid accumulators (semi-lead accumulators H01M10/20) · CPC title

• H01M50/505

  comprising a single busbar · CPC title

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M2220/20

  Batteries in motive systems, e.g. vehicle, ship, plane · CPC title

• B60L7/16 Primary

  for vehicles comprising converters between the power source and the motor · CPC title