Apparatus and method for identifying alternative cell chemistries for batteries
New and useful systems, methods, and apparatuses for automatically identifying alternative cell chemistries of batteries that power portable electric devices and adjusting the characteristics of such devices in response to the identification of such cells in a reduced-pressure therapy environment are set forth in the appended claims.
1. A system for treating a tissue site with reduced pressure including an electronic device for identifying the cell chemistry of a battery inserted therein, the system comprising:
a dressing including a manifold for providing a reduced-pressure treatment space to the tissue site, a sealing member for sealing the manifold within the reduced-pressure treatment space, and a reduced-pressure interface coupled to the sealing member for providing reduced pressure to the manifold;
a reduced-pressure source including a vacuum pump and a motor for driving the vacuum pump, the vacuum pump fluidly coupled to the reduced-pressure interface to provide reduced pressure to the manifold;
a motor drive having an input and an output operatively coupled to the motor;
a test circuit including a resistor and a switch electrically connected in series and having two electrical contacts configured to be connected to the battery when inserted into the electronic device, the switch being actionable between an open position to provide an open circuit voltage (V O ) of the battery and a closed position to provide a load voltage (V L ) of the resistor, the test circuit having an output providing a battery-identifier output signal including the open circuit voltage (V O ) and the load voltage (V L ); and
a controller electrically coupled to the output of the test circuit and the input of the motor drive, the controller being responsive to the battery-identifier output signal and configured to selectively adjust the aggression of the motor drive as determined by the cell chemistry of the battery and identified by the battery-identifier output signal.
2. The system of claim 1 , wherein the test circuit further comprises a computer having a program for determining whether the electronic device has been powered up by the battery, measuring the open circuit voltage (V O ) of the battery, measuring the load voltage (V L ) of the resistor, calculating a percent voltage drop (V L /V O ) resulting from connecting the resistor to the battery, and using these three values in connection with an algorithm to determine the cell chemistry of the battery for providing the battery-identifier output signal.
3. The system of claim 2 , wherein the algorithm determines that the battery has a lithium cell chemistry if V O is greater than or equal to 1.65V and V L is greater than or equal to 0.55V O and provides the battery identifier output signal to the controller which adjusts a characteristic of the electronic device to function with a battery having a lithium cell chemistry.
4. The system of claim 2 , wherein the algorithm determines that the battery has a zinc carbon cell chemistry if V L is less than 0.45V O and provides the battery identifier output signal to the controller which adjusts a characteristic of the electronic device to function with a battery having a zinc carbon cell chemistry.
5. The system of claim 2 , wherein the algorithm determines that the battery has an alkaline cell chemistry if V L is less than 0.55V O but greater than 0.45V O and provides the battery identifier output signal to the controller which adjusts a characteristic of the electronic device to function with a battery having an alkaline cell chemistry.
6. The system of claim 1 , wherein the battery comprises one or more cells (n), the resistor has a resistance of R, and when the switch is turned to the closed position, the resistor has a resistance of 0.25R(n).
7. The system of claim 1 , wherein the load voltage (V L ) of the resistor is measured only once.