Series-connected battery packs, system and method

Abstract

A power device including a housing, charging circuitry, and discharge circuitry. The housing defining a first support operable to support a first battery pack, and a second support operable to support a second battery pack. The charging circuitry electrically is connected to the first battery pack and the second battery pack in a parallel-type connection. The charging circuitry is configured to simultaneously charge the first battery pack and the second battery pack. The discharge circuitry is electrically connected to the first battery pack and the second battery pack. The discharge circuitry is configured to electrically connect the first battery pack and the second battery pack in a series-type connection during a discharge

What is claimed is: 
     
         1 . A power device comprising:
 a housing defining a first support operable to support a first battery pack, and a second support operable to support a second battery pack;   a motor receiving power across a phase of the motor from at least one of the first battery pack and the second battery pack; and   a circuit selectively electrically connecting the first battery pack and the second battery pack to the motor, the circuit including:
 a first motor drive circuit connecting the first battery pack to the motor, 
 a second motor drive circuit connecting the second battery pack to the motor, and 
 an output terminal to provide at least one of a first power output of the first battery pack and a second power output of the second battery pack to the motor, wherein the first power output is provided to the motor based on a first characteristic of the first battery pack and the second power output is provided to the motor based on a second characteristic of the second battery pack. 
   
     
     
         2 . The power device of  claim 1 , wherein the circuit is configured to selectively electrically connect the first battery pack and the second battery pack with the motor in at least one of a series-type connection and a parallel-type connection. 
     
     
         3 . The power device of  claim 1 , wherein the circuit is configured to selectively electrically connect the first battery pack and the second battery pack with the motor in at least one of a series-type connection and a parallel-type connection based on the first characteristic of the first battery pack and the second characteristic of the second battery pack. 
     
     
         4 . The power device of  claim 1 , wherein the circuit is configured to selectively electrically connect the first battery pack and the second battery pack with the motor in at least one of a series-type connection and a parallel-type connection to provide a defined power output to the motor based on a defined runtime of the motor. 
     
     
         5 . The power device of  claim 1 , wherein the first characteristic of the first battery pack and the second characteristic of the second battery pack are selected from a group consisting of: a nominal voltage, a capacity, and a state of charge. 
     
     
         6 . The power device of  claim 5 , wherein the first battery pack has a first state of charge, and the second battery pack has a second state of charge different than the first state of charge. 
     
     
         7 . The power device of  claim 5 , wherein the first battery pack has a first capacity and a first nominal voltage, and the second battery pack has a second capacity and a second nominal voltage, and wherein at least one of the second capacity or the second nominal voltage is different than the first capacity or the first nominal voltage. 
     
     
         8 . The power device of  claim 1 , further comprising a DC-DC converter bypass element. 
     
     
         9 . A method of powering a motor of a power device, the method comprising:
 receiving, via a first support, a first battery pack;   receiving, via a second support, a second battery pack;   determining a first characteristic of the first battery pack and a second characteristic of the second battery pack;   selectively electrically connecting, via a circuit, the first battery pack and the second battery pack to the motor, wherein a first motor drive circuit of the circuit connects the first battery pack to the motor, and a second motor drive circuit of the circuit connects the second battery pack to the motor; and   providing, via an output terminal of the circuit, power from at least one of the of the first battery pack and the second battery pack to the motor across a phase of the motor based on the first characteristic of the first battery pack and the second characteristic of the second battery pack.   
     
     
         10 . The method of  claim 9 , wherein selectively electrically connecting, via the circuit, the first battery pack and the second battery pack to the motor, further comprises:
 selectively electrically connecting the first battery pack and the second battery pack with the motor in at least one of a series-type connection and a parallel-type connection.   
     
     
         11 . The method of  claim 9 , wherein selectively electrically connecting, via the circuit, the first battery pack and the second battery pack to the motor, further comprises:
 selectively electrically connecting the first battery pack and the second battery pack with the motor in at least one of a series-type connection and a parallel-type connection based on the first characteristic of the first battery pack and the second characteristic of the second battery pack.   
     
     
         12 . The method of  claim 9 , wherein selectively electrically connecting, via the circuit, the first battery pack and the second battery pack to the motor, further comprises:
 selectively electrically connecting the first battery pack and the second battery pack with the motor in at least one of a series-type connection and a parallel-type connection to provide a defined power output to the motor based on a defined runtime of the motor.   
     
     
         13 . The method of  claim 9 , wherein the first characteristic of the first battery pack and the second characteristic of the second battery pack are selected from a group consisting of: a nominal voltage, a capacity, and a state of charge. 
     
     
         14 . The method of  claim 13 , wherein the first characteristic of the first battery pack is different than the second characteristic of the second battery pack. 
     
     
         15 . A system comprising:
 a first battery pack including a first battery pack housing and a first battery cell contained within the housing;   a second battery pack including a second battery pack housing and a second battery cell contained within the housing; and   a power device including:
 a motor, 
 a power device housing defining a first support operable to support the first battery pack housing, and a second support operable to support the second battery pack housing, 
 a circuit electrically connected to the first battery pack and the second battery pack, the circuit including a first motor drive circuit connecting the first battery pack to the motor, a second motor drive circuit connecting the second battery pack to the motor, and an output terminal to provide at least one of a first power output of the first battery pack and a second power output of the second battery pack to the motor, the circuit configured to selectively electrically connect the first battery pack and the second battery pack to the motor; 
 wherein the first power output of the first battery pack is based on a first characteristic of the first battery pack and the second power output provided by the second battery pack is based on a second characteristic of the second battery pack, and 
 wherein the circuit is controlled to provide power to the motor across a phase of the motor from at least one of the of the first battery pack and the second battery pack. 
   
     
     
         16 . The system of  claim 15 , wherein the circuit is configured to selectively electrically connect the first battery pack and the second battery pack with the motor in at least one of a series-type connection and a parallel-type connection. 
     
     
         17 . The system of  claim 15 , wherein the circuit is configured to selectively electrically connect the first battery pack and the second battery pack with the motor in at least one of a series-type connection and a parallel-type connection based on the first characteristic of the first battery pack and the second characteristic of the second battery pack. 
     
     
         18 . The system of  claim 15 , wherein the circuit is configured to selectively electrically connect the first battery pack and the second battery pack with the motor in at least one of a series-type connection and a parallel-type connection to provide a defined power output to the motor based on a defined runtime of the motor. 
     
     
         19 . The system of  claim 15 , wherein the first characteristic of the first battery pack and the second characteristic of the second battery pack are selected from a group consisting of: a nominal voltage, a capacity, and a state of charge. 
     
     
         20 . The system of  claim 15 , wherein the circuit includes a DC-DC converter bypass element.