Controlling electrical access to a lithium battery on a utility vehicle

Patent metadata

Field	Value
Publication number	US-10933755-B2
Application number	US-201916407329-A
Country	US
Kind code	B2
Filing date	May 9, 2019
Priority date	Dec 30, 2016
Publication date	Mar 2, 2021
Grant date	Mar 2, 2021

Abstract

Techniques involve managing lithium battery access on a utility vehicle. In accordance with such techniques, a wakeup circuit includes a set of inputs, a set of outputs, and control logic coupled with the set of inputs and the set of outputs. The control logic is constructed and arranged to, in response to detecting a wakeup event from circuitry of the utility vehicle via the set of inputs, close a switching apparatus of the utility vehicle via the set of outputs to connect a lithium battery of the utility vehicle to a set of loads of the utility vehicle. The control logic is further constructed and arranged to, in response to detecting a sleep event, open the switching apparatus via the set of outputs to disconnect the lithium battery of the utility vehicle from the set of loads of the utility vehicle.

First claim

What is claimed is:

1. A wakeup circuit that manages lithium battery access on a utility vehicle, the wakeup circuit comprising:
a set of inputs;
a set of outputs;
control logic coupled with the set of inputs and the set of outputs, the control logic being constructed and arranged to:
in response to detecting a wakeup event from circuitry of the utility vehicle via the set of inputs, close a switching apparatus of the utility vehicle via the set of outputs to connect a lithium battery of the utility vehicle to a set of loads of the utility vehicle, and
in response to detecting a sleep event, open the switching apparatus via the set of outputs to disconnect the lithium battery of the utility vehicle from the set of loads of the utility vehicle; and

a timer coupled to the control logic, the timer being constructed and arranged to measure utility vehicle inactivity time and identify a sleep event when the utility vehicle inactivity time reaches a predefined inactivity time threshold;
wherein the wakeup circuit is constructed and arranged to reset the timer to re-start measuring utility vehicle inactivity time in response to vehicle activity sensed via the set of inputs.

2. A wakeup circuit as in claim 1 wherein the circuitry of the utility vehicle includes a maintenance switch; and
wherein the control logic is constructed and arranged to:
while the control logic is initially in a sleep mode and the lithium battery is disconnected from the set of loads of the utility vehicle, detect, as a particular wakeup event and via the set of inputs, a transition of the maintenance switch from an OFF position to an ON position, and
in response to the particular wakeup event, transition from the sleep mode to an awake mode and, while the control logic is in the awake mode, output a control signal on the set of outputs, the control signal closing the switching apparatus to connect the lithium battery of the utility vehicle to the set of loads of the utility vehicle.

3. A wakeup circuit as in claim 2 wherein the circuitry of the utility vehicle further includes a keyed switch; and
wherein the control logic is constructed and arranged to:
after the control logic has returned to the sleep mode and while the maintenance switch remains in the ON position and the lithium battery is disconnected from the set of loads of the utility vehicle, detect, as a second wakeup event and via the set of inputs, a transition of the keyed switch from an OFF position to an ON position, and
in response to the second wakeup event, transition from the sleep mode to the awake mode and, while the control logic is in the awake mode, output the control signal on the set of outputs, the control signal closing the switching apparatus to re-connect the lithium battery of the utility vehicle to the set of loads of the utility vehicle.

4. A wakeup circuit as in claim 3 wherein the circuitry of the utility vehicle further includes a pedal; and
wherein the control logic is constructed and arranged to:
after the control logic has returned to the sleep mode and while the maintenance switch remains in the ON position, the keyed switch remains in the ON position and the lithium battery is disconnected from the set of loads of the utility vehicle, detect, as a third wakeup event and via the set of inputs, depression of the pedal, and
in response to the third wakeup event, transition from the sleep mode to the awake mode and, while the control logic is in the awake mode, output the control signal on the set of outputs, the control signal closing the switching apparatus to re-connect the lithium battery of the utility vehicle to the set of loads of the utility vehicle.

5. A wakeup circuit as in claim 1 wherein the wakeup circuit is constructed and arranged to:
sense current drawn from the lithium battery, and
indicate that a wakeup event has occurred in response to the current drawn from the lithium battery exceeding a predefined current threshold.

6. A wakeup circuit as in claim 1 wherein the circuitry of the utility vehicle includes a keyed switch; and
wherein the control logic is constructed and arranged to:
while the control logic is initially in a sleep mode and the lithium battery is disconnected from the set of loads of the utility vehicle, detect, as a particular wakeup event and via the set of inputs, a transition of the keyed switch from an OFF position to an ON position, and
in response to the particular wakeup event, transition from the sleep mode to an awake mode and, while the control logic is in the awake mode, output a control signal on the set of outputs, the control signal closing the switching apparatus to connect the lithium battery of the utility vehicle to the set of loads of the utility vehicle.

7. A wakeup circuit as in claim 1 wherein the circuitry of the utility vehicle includes a pedal; and
wherein the control logic is constructed and arranged to:
while the control logic is initially in a sleep mode and the lithium battery is disconnected from the set of loads of the utility vehicle, detect, as a particular wakeup event and via the set of inputs, depression of the pedal, and
in response to the particular wakeup event, transition from the sleep mode to an awake mode and, while the control logic is in the awake mode, output a control signal on the set of outputs, the control signal closing the switching apparatus to connect the lithium battery of the utility vehicle to the set of loads of the utility vehicle.

8. A wakeup circuit that manages lithium battery access on a utility vehicle, the wakeup circuit comprising:
a set of inputs;
a set of outputs;
control logic coupled with the set of inputs and the set of outputs, the control logic being constructed and arranged to:
in response to detecting a wakeup event from circuitry of the utility vehicle via the set of inputs, close a switching apparatus of the utility vehicle via the set of outputs to connect a lithium battery of the utility vehicle to a set of loads of the utility vehicle, and
in response to detecting a sleep event, open the switching apparatus via the set of outputs to disconnect the lithium battery of the utility vehicle from the set of loads of the utility vehicle;

wherein the circuitry of the utility vehicle includes a receptacle; and
wherein the control logic is constructed and arranged to:
while the control logic is initially in a sleep mode and the lithium battery is disconnected from the set of loads of the utility vehicle, detect, as a particular wakeup event and via the set of inputs, connection of a charger to the receptacle, and
in response to the particular wakeup event, transition from the sleep mode to an awake mode and, while the control logic is in the awake mode, output a control signal on the set of outputs, the control signal closing the switching apparatus to connect the lithium battery of the utility vehicle to the set of loads of the utility vehicle.

9. A wakeup circuit as in claim 8 wherein the receptacle couples with the switching apparatus; and
wherein, in response to the control logic outputting the control signal and the switching apparatus closing to connect the lithium battery to the set of loads, the charger delivers charge to the lithium battery through the switching apparatus while the control logic outputs the control signal on the set of outputs.

10. A wakeup circuit as in claim 9 wherein the control logic is further constructed and arranged to:
after the lithium battery charges to a predefined charge threshold, open the switching apparatus to discontinue delivery of charge from the charger to the lithium battery.

11. A battery management system that manages lithium battery ac

Assignees

• Textron Innovations Inc

Inventors

• Harvey Arthur James
• Padgett Norman R
• Ledden John
• Bradley Robert Charles
• Warden Patrick Dwaine

Classifications

• H02J7/933

  the cycle being controlled or terminated in response to electric parameters · CPC title

• H02J7/927

  with introduction of pulses during the charging process · CPC title

• H02J7/585

  Sequential battery discharge in systems with a plurality of batteries · CPC title

• B60L58/14 Primary

  Preventing excessive discharging · CPC title

• B60W2510/08

  Electric propulsion units · CPC title