FIELD

The present invention relates to battery packs and electrical devices connectable to battery packs and, more particularly, to a terminal configuration for a battery pack and/or an electrical device.

SUMMARY

Tools, such as power tools (e.g., drills, drivers, saws, etc.), outdoor tools (e.g., blowers, trimmers, etc.), etc., and other electrical devices (e.g., motorized devices, non-motorized devices, chargers, etc.) (generally referred to herein as “devices” or a “device”) may transfer power (e.g., be powered by, supply power to) with rechargeable battery packs. The battery pack may be detached from a device for charging or for use with other devices. In many cases, battery packs are designed such that the same battery pack may be used with many kinds of devices.

Battery packs include a number of battery cells (for example, Li-ion, NiCd, NiMH, etc.) connected in a series configuration, a parallel configuration, or a combination thereof. Power terminals are connected to the battery cells. When a battery pack is connected to a device, the power terminals of the battery pack are connected to corresponding power terminals of the device, and the battery pack provides operating power to the device through the power terminals.

Many electrical devices include a controller to monitor and control operation (e.g., motor speed, torque output, etc.) of the device. Similarly, many battery packs include a controller to monitor and control operation (e.g., charging and discharging operations, display state-of-charge, etc.).

While the device controller and the battery pack controller generally operate independently of each other, communication between the controllers may be advantageous. For example, the controllers may communicate to adjust operation based on a characteristic of the device and/or of the battery pack. As another example, the device controller may communicate with the battery pack controller to authenticate the battery pack, thereby improving the operation and security of the devices.

In some embodiments, the power terminals may be used to provide communication between the device controller and the battery pack controller. However, this may result in noise being generated on the communication line between the controllers. In addition, the amount of information that may be exchanged may be limited by the number of terminals. Accordingly, separate communication terminals that are isolated from the power terminals may be needed to provide a low-noise communication line with sufficient information capacity between the device controller and the battery pack controller.

In addition, the power received from the battery pack is used to power both the load (e.g., the motor) and the device controller. While controllers used in electrical devices generally have low power requirements, they do consume power. As such, the device controller may be put into a sleep mode to avoid unnecessarily draining the battery pack to constantly power the device controller.

Electrical device controllers also generally have low power capacity. For example, a device load (e.g., a motor) may operate in a range of 25-35 Amps (A) or more. In contrast, a device controller may operate at well under 1 A. When initiating operation of an electrical device, it may be desirable to provide low power to “wake-up” the device controller before the full voltage of the battery pack is provided to power the electrical device.

In some embodiments, a separate dedicated battery (e.g., a coin cell) may be used to power low power functions of the electrical device or the battery pack. The dedicated battery may be used separately from the battery pack to power the device controller. However, such a dedicated battery adds a separate non-chargeable or non-replaceable component to the electrical device.

In other embodiments, low power may be provided to the electrical device through a low-power circuit connected across a single battery of the battery pack. However, this may result in cell balancing issues, as one battery cell (the “low-power cell”) is drained more often than the other battery cells in the battery pack, reducing the service life of the battery pack. In order to avoid these issues, the single cell low power application may be limited to very low power and infrequent operations.

Accordingly, a relatively low-power power source may be needed to power recurring low power functions of the electrical device without incurring performance or service life issues (e.g., due to cell imbalances) or adding additional non-chargeable, non-replaceable components to the battery pack or electrical device. A low-power power supply may be advantageous in powering other low-power components of an electrical device, such as an indicator/LED, a communication module, etc.

In one independent aspect, a battery pack may generally include a housing; a plurality of battery cells supported by the housing; a plurality of terminals including a positive power terminal, a negative power terminal, and a low power terminal; a low power circuit connecting the plurality of battery cells to the low power terminal and the negative terminal to output a first voltage; and a power circuit connecting the plurality of battery cells to the positive power terminal and the negative terminal to output a second voltage, the second voltage being greater than the first voltage (e.g., 80 V compared to 5 V).

In some embodiments, the low power circuit may include a transformer (e.g., a step down transformer or a low dropout regulator (LDO)). In some embodiments, the battery pack may include a controller operable to control the battery pack to selectively output the first voltage and the second voltage.

In another independent aspect, a method of operating a battery-powered device with a battery pack may be provided. The device may include a device housing, a load supported by the device housing, and a device controller supported by the device housing. The battery pack may include a pack housing, and a plurality of battery cells supported by the housing. The method may generally include supplying a first voltage from the plurality of battery cells to the device to power the device controller; and supplying a second voltage from the plurality of battery cells to the device to power the device. Supplying a first voltage may include, with a transformer (e.g., a step down transformer or a low dropout regulator (LDO)), reducing a voltage of the plurality of battery cells to the first voltage.

In yet another independent aspect, a battery pack may generally include a housing; a plurality of battery cells supported by the housing; a controller; and a plurality of terminals including a positive power terminal, a negative power terminal and a communication terminal, the communication terminal being electrically connected to the controller and operable to communicate between the controller and an external device, the communication terminal being isolated from the positive power terminal and the negative power terminal.

In some embodiments, the housing may include a terminal block supporting the plurality of terminals, the positive power terminal and the negative terminal being arranged in a first row, the communication terminal being arranged in a second row spaced from the first row.

In a further independent aspect, an electrical combination may generally include an electrical device including a device housing, a load supported by the device housing, a device controller supported by the device housing, and a plurality of device terminals including a device positive power terminal, a device negative terminal, and a device low power terminal; and a battery pack including a pack housing; a plurality of battery cells supported by the pack housing, a plurality of pack terminals including a pack positive power terminal electrically connectable to the device positive power terminal, a pack negative power terminal electrically connectable to the device negative terminal, and a pack low power terminal electrically connectable to the device low power terminal, a low power circuit connecting the plurality of battery cells to the low power terminal and the pack negative terminal to output a first voltage to power the device controller, and a power circuit connecting the plurality of battery cells to the pack positive power terminal and the pack negative terminal to output a second voltage to power the load, the second voltage being greater than the first voltage.

In another independent aspect, a terminal for one of a battery pack and an electrical device electrically connectable to the battery pack along an axis may be provided. The terminal may generally include a terminal blade extending along the axis and having opposite axially-extending faces connected by opposite axially-extending edges; and a terminal support portion extending transverse to the axis and beyond an associated face.

In some embodiments, the terminal support portion may include a transverse wing connected to one edge. In some embodiments, the support portion includes at least one rib on the associated face.

In yet another independent aspect, a terminal block for one of a battery pack and an electrical device electrically connectable to the battery pack along an axis may be provided. The terminal block may generally include a housing; and a plurality of terminals including a positive power terminal and a ground terminal, at least one terminal including a terminal blade extending along the axis and having opposite axially-extending faces connected by opposite axially-extending edges, and a terminal support portion extending transverse to the axis and beyond an associated face.

In a further independent aspect, an electrical combination may generally include a battery pack including a pack housing, a plurality of battery cells supported by the pack housing, and a pack terminal electrically connected to the battery cells; and an electrical device including a device housing, a circuit supported by the device housing, and a device terminal electrically connected to the circuit and electrically connectable to the pack terminal to electrically connect the circuit to one or more battery cells; one of the pack terminal and the device terminal including a terminal blade extending along the axis and having opposite axially-extending faces connected by opposite axially-extending edges, and a terminal support portion extending transverse to the axis and beyond an associated face.

Other independent aspects of the invention may become apparent by consideration of the detailed description, claims and accompanying drawings.

