US-12627013-B2 - Battery pack detection and battery discharge mode selection

Abstract

A power tool including a battery pack interface configured to receive a battery pack. The battery pack interface includes one or more power terminals and one or more communication terminals. The power tool further includes a controller having an electronic processor. The controller is configured to receive, via the one or more communication terminals, a plurality of signals indicating a plurality of temperatures of the battery pack. The controller is further configured to determine, based on the signals, a battery pack type. The controller is further configured to control discharge of the battery pack based on the battery pack type.

Inventors

• Jay Rosenbecker
• Randolph McHugh
• Fraizier Reiland

Assignees

• MILWAUKEE ELECTRIC TOOL CORPORATION

Dates

Publication Date

20260512

Application Date

20241115

Claims (20)

1. 1 . A power tool comprising: a controller including an electronic processor and a memory, the controller configured to: determine a slope indicating a change in temperature of a battery pack over a period of time, determine, based on the slope, a battery pack type, and control a discharge of the battery pack based on the battery pack type.
2. 2 . The power tool of claim 1 , wherein the discharge of the battery pack includes a constant power.
3. 3 . The power tool of claim 1 , wherein the discharge of the battery pack includes a step function of decreasing power.
4. 4 . The power tool of claim 1 , wherein the discharge of the battery pack includes a series of decreasing ramp functions.
5. 5 . The power tool of claim 1 , wherein the battery pack is configured to be discharged at a first power for a first period of time, the discharge is configured to be decreased from the first power to a second power over a second period of time, and the battery pack is configured to discharge at a third power over a third period of time.
6. 6 . The power tool of claim 1 , wherein the slope is determined based on a plurality of signals received from a thermistor of the battery pack.
7. 7 . The power tool of claim 1 , wherein the controller is further configured to receive one or more signals from the battery pack related to the slope.
8. 8 . The power tool of claim 1 , wherein, to determine the slope, the controller is further configured to: receive a first signal indicating a first temperature of the battery pack; receive a second signal indicating a second temperature of the battery pack; and subtract the second temperature from the first temperature.
9. 9 . The power tool of claim 8 , wherein the controller is further configured to: compare the slope to a predetermined slope to determine the battery pack type.
10. 10 . A battery pack comprising: at least one battery cell; a discharge circuit configured to discharge current from the at least one battery cell to an electronic device; and a thermistor configured to detect a temperature of the battery pack, wherein the battery pack is configured to provide one or more signals to the electronic device indicative of a change in the temperature of the battery pack over a period of time in order to determine a type of the battery pack for controlling the discharge current of the battery pack based on the type of the battery pack.
11. 11 . The battery pack of claim 10 , wherein the discharge current of the battery pack includes a constant power.
12. 12 . The battery pack of claim 10 , wherein the discharge current of the battery pack includes a ramp function of decreasing power.
13. 13 . The battery pack of claim 10 , wherein the discharge current of the battery pack includes a step function of decreasing power.
14. 14 . The battery pack of claim 10 , wherein the battery pack is configured to discharge at a first power for a first period of time, the discharge is configured to be decreased from the first power to a second power over a second period of time, and the battery pack is configured to discharge at a third power over a third period of time.
15. 15 . The battery pack of claim 10 , wherein the change in the temperature of the battery pack over the period of time is a slope of the temperature of the battery pack, and the slope of the temperature of the battery pack corresponds to the type of the battery pack.
16. 16 . A method of determining a battery pack type, the method comprising: determining a slope indicating a change in temperature of a battery pack over a period of time; determining, based on the slope, the battery pack type; and controlling, based on the battery pack type, a discharge cycle of the battery pack.
17. 17 . The method of claim 16 , wherein determining the slop includes receiving a plurality of temperature signals from a thermistor of the battery pack.
18. 18 . The method of claim 16 , wherein determining the slope includes: receiving a first signal indicating a first temperature of the battery pack; receiving a second signal indicating a second temperature of the battery pack; and subtracting the second temperature from the first temperature.
19. 19 . The method of claim 16 , further comprising: comparing the slope to a predetermined slope.
20. 20 . The method of claim 16 , further comprising: discharging the battery pack at a first power for a first period of time, decreasing discharging from the first power to a second power over a second period of time, and discharging the battery pack at a third power over a third period of time.

Description

RELATED APPLICATIONS This application is a continuation of U.S. patent application Ser. No. 18/301,423, filed Apr. 17, 2023, which is a continuation of U.S. patent application Ser. No. 16/951,516, filed Nov. 18, 2020, now U.S. Pat. No. 11,631,926, which claims the benefit of U.S. Provisional Patent Application No. 62/940,583, filed Nov. 26, 2019, the entire content of each of which is hereby incorporated by reference. FIELD Embodiments described herein relate to electrical devices powered by one or more batteries and/or battery packs. SUMMARY Battery packs may include a temperature sensor, such as a thermistor, for determining the temperature of the device as the device is charged or discharged. These temperature sensors may be used for protection measures, such as stopping charge or discharge when a temperature passes a threshold. Power tools described herein include a battery pack interface configured to receive a battery pack. The battery pack interface includes one or more power terminals and one or more communication terminals. The power tools further include a controller having an electronic processor. The controller is configured to receive, via the one or more communication terminals, a plurality of signals indicating a plurality of temperatures of the battery pack. The controller is further configured to determine, based on the signals, a battery pack type. The controller is further configured to control discharge of the battery pack based on the battery pack type. In some embodiments, the discharge of the battery pack includes a constant power. In some embodiments, the discharge of the battery pack includes a step function of decreasing power. In some embodiments, the discharge of the battery pack includes a series of decreasing ramp functions. In some embodiments, the battery pack discharges at a first power for a first period of time, decreases from the first power to a second power over a second period of time, and discharges at a third power over a third period of time. In some embodiments, the plurality of signals indicating a temperature of the battery pack is provided by a thermistor of the battery pack. In some embodiments, the plurality of signals indicating a temperature of the battery pack are equal in value. In some embodiments, determining the battery pack type further includes receiving a first signal of the plurality of signals indicating a temperature of the battery pack, receiving a second signal of the plurality of signals indicating a temperature of the battery pack, and determining a slope of the plurality of signals by subtracting the second signal from the first signal. In some embodiments, the step of determining, based on the plurality of signals, the battery pack type further includes comparing the slope of the plurality of signals to a predetermined slope. Battery packs described herein include a housing, at least one battery cell contained within the housing, and a battery pack interface configured to connect to an electronic device. The battery pack interface includes one or more power terminals and one or more communication terminals. The battery packs further include a discharge circuit configured to discharge current from the battery cells to the one or more terminals of the battery interface. The battery packs also include a thermistor configured to provide a plurality of signals indicating a plurality of temperatures of the battery pack to the one or more communication terminals of the battery pack interface. The plurality of signals are provided to the electronic device to determine a type of the battery pack for controlling discharge of the battery pack based on the type of the battery pack. In some embodiments, the discharge of the battery pack includes a constant power. In some embodiments, the discharge of the battery pack includes a ramp function of decreasing power. In some embodiments, the plurality of signals indicating a temperature of the battery pack is provided by a thermistor of the battery pack. In some embodiments, the plurality of signals indicating a temperature of the battery pack are equal in value. In some embodiments, determining the battery pack type further includes comparing a slope of the plurality of signals to a predetermined slope. Methods described herein provide for determining a battery pack type. The methods include receiving, by a battery pack interface of a power tool, a battery pack. The methods further include receiving, by one or more communication terminals of the battery pack interface, a plurality of signals indicating a plurality of temperatures of the battery pack. The method further includes determining, based on the plurality of signals, the battery pack type. The methods further include controlling, based on the battery pack type, a discharge cycle of the battery pack. In some embodiments, the plurality of signals indicating a temperature of the battery pack is provided by a thermistor of the battery pack. In some embod