Battery charging

• US 4,234,839 A
• Filed: 11/01/1978
• Issued: 11/18/1980
• Est. Priority Date: 11/08/1977
• Status: Expired due to Term

• Current Assignee: Bowman; Noel Trevor, King; Christopher Duff, Sally King
• Original Assignee: Bowman; Noel Trevor, King; Christopher Duff, Sally King
• Inventors: King, Christopher D., Bowman, Noel T.
• Primary Examiner(s): Hickey, Robert J.
• Application Number:
  US05/956,823
• Time in Patent Office: 748 Days
• Field of Search: 320/35, 320/36, 320/2
• US Class Current: 320/150
• CPC Class Codes: B60L 2200/42 Fork lift trucks
• CPC Class Codes: B60L 2240/545 Temperature
• CPC Class Codes: B60L 2240/549 Current
• CPC Class Codes: B60L 3/0046 relating to electric energy storage systems, e.g. batteries or capacitors
• CPC Class Codes: B60L 3/04 Cutting off the power supply under fault conditions protective devices and circuit arrangements in general H01H; H02H
• CPC Class Codes: B60L 53/22 Constructional details or arrangements of charging converters specially adapted for charging electric vehicles
• CPC Class Codes: B60L 58/10 for monitoring or controlling batteries
• CPC Class Codes: B60L 58/24 for controlling the temperature of batteries
• CPC Class Codes: H01M 10/443 in response to temperature
• CPC Class Codes: H01M 2200/10 Temperature sensitive devices
• CPC Class Codes: H02J 7/007194 of the battery
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles

Abstract

A battery charging system is disclosed wherein there is control means connected with a battery charger responsive to the temperature of a temperature sensor connected with a battery to sense its temperature whereby to switch off the charging when the battery temperature is at or above a predetermined temperature unsuitable for charging. The control means includes a signal transmitter and a signal receiver. The signal transmitter applies a pulsed signal to the charging leads when the temperature of the battery is at or above the predetermined temperature and the receiver detects this and switches off the charging. A signal transmitter and temperature sensor, and a battery fitted therewith is also disclosed.

Claims

1. A battery charging system comprising a charging circuit, battery temperature sensing means and charging circuit control means operatively connected with the battery temperature sensing means to stop charging when the temperature sensing means senses that the temperature of a battery being charged is at or above a predetermined temperature unsuitable for charging, and wherein the charging circuit control means includes a signal transmitter and a signal receiver and wherein the transmitter generates and transmits a signal when the temperature of the temperature sensing means is above a predetermined value and the receiver detects such signal and switches off the charging circuit and wherein during charging the signal transmitter and the signal receiver are continuously powered by DC which is on charging leads connected between said charging circuit and said battery, said signal transmitter being connected to the battery terminals and said temperature sensing means being connected to the battery so that when the charging leads are removed the signal transmitter and the temperature sensing means remain connected to the battery terminals as a unitary structure.

2. A battery charging system comprising a charging circuit, battery temperature sensing means and charging circuit control means operatively connected with the battery temperature sensing means to stop charging when the temperature sensing means senses that the temperature of a battery being charged is at or above a predetermined temperature unsuitable for charging and wherein the charging circuit control means includes a signal transmitter and a signal receiver and wherein the transmitter generates and transmits a signal when the temperature of the temperature sensing means is above a predetermined value and the receiver detects such signal and switches off the charging circuit and wherein during charging the signal transmitter and the signal receiver are continuously powered by DC which is on charging leads connected between said charging circuit and said battery and wherein the signal transmitter is connected to the battery terminals and the temperature sensing means is connected to the battery so that when the charging leads are removed the signal transmitter and the temperature sensing means remain connected to the battery terminals as a unitary structure and wherein the signal transmitter is arranged to apply a pulsed signal onto the charging leads when the temperature of the battery is at or above the predetermined temperature, and wherein the signal receiver is arranged to detect the presence of the pulsed signal on the charging leads and to switch off the charging current to the battery on such detection.

3. A battery charging system as claimed in claim 2 wherein the temperature sensing means is a temperature dependent resistance wired so that as the resistance changes the potential thereacross changes and wherein the signal transmitter has a voltage comparator means which receives the voltage across said temperature dependent resistance and compares it against a predetermined reference voltage so that when there is a difference representative of the temperature being at or above the predetermined temperature, the voltage comparator provides an output signal to an oscillator to cause it to oscillate to in turn switch on a transistor switch at a rate equal to the oscillation frequency of the oscillator whereby to short the charging leads through a resistor and a parallel connected condenser at the oscillator frequency to provide said pulsed signal.

4. A battery charging system comprising a charging circuit, battery temperature sensing means and charging circuit control means operatively connected with the battery temperature sensing means to stop charging when the temperature sensing means senses that the temperature of a battery being charged is at or above a predetermined temperature unsuitable for charging and wherein the charging circuit control means includes a signal transmitter and a signal receiver and wherein the transmitter generates and transmits a signal when the temperature of the temperature sensing means is above a predetermined value and the receiver detects such signal and switches off the charging circuit and wherein during charging the signal transmitter and the signal receiver are continuously powered by DC which is on charging leads connected between said charging circuit and said battery and wherein the signal transmitter is connected to the battery terminals and the temperature sensing means is connected to the battery so that when the charging leads are removed the signal transmitter and the temperature sensing means remain connected to the battery terminals as a unitary structure and wherein the signal transmitter is arranged to apply a pulsed signal onto the charging leads when the temperature of the battery is at or above the predetermined temperature, and wherein the signal receiver is arranged to detect the presence of the pulses signal on the charging leads and to switch off the charging current to the battery on such detection and wherein the temperature sensing means is a temperature dependent resistance wired so that as the resistance changes the potential thereacross changes and wherein the signal transmitter has a voltage comparator means which receives the voltage across said temperature dependent resistance and compares it against a predetermined reference voltage so that when there is a difference representative of the temperature being at or above the predetermined temperature, the voltage comparator provides an output signal to an oscillator to cause it to oscillate to in turn switch on a transistor switch at a rate equal to the oscillation frequency of the oscillator whereby to short the charging leads through a resistor and a parallel connected condenser at the oscillator frequency to provide said pulsed signal and wherein said signal receiver has a high-pass filter for passing said pulsed signal, a monostable circuit for receiving said pulsed signal from said high pass filter and for stretching the duration of the pulses, a low-pass filter for receiving the stretched pulses and for averaging the voltage of the pulses, a voltage comparator connected to receive said averaged voltage and arranged to compare said averaged voltage with a reference voltage and to provide a signal output when the averaged voltage is greater than said reference voltage, a transistor switch connected to receive said signal output and to apply a current to a relay to operate said relay to disconnect the charging current from said charging leads.

5. A signal transmitter and temperature sensor for connection to a battery terminals to provide a pulsed signal at the battery terminals when the temperature of the battery is at or above a predetermined temperature unsuitable for charging, said temperature sensor being connectable to said battery to measure the temperature thereof, and said signal transmitter comprises means connected to said temperature sensor to obtain a voltage thereacross which varies in accordance with the temperature of said battery voltage comparator means for comparing the voltage thereacross with a predetermined reference voltage and for providing an output signal if the voltage thereacross is greater than said predetermined reference voltage representative of the battery temperature being at or above said predetermined temperature, an oscillator connected to said voltage comparator to receive said output signal and to cause it to oscillate in response to receipt of said output signal, and a transistor switch arranged to short the battery through a parallel connected resistor and condenser at the frequency of oscillation of said oscillator, whereby to apply said pulsed signal to said battery terminals.