2382results about "Battery overdischarge protection" patented technology

An intelligent rechargeable battery pack having a battery management system for monitoring and controlling the charging and discharging of the battery pack is described. The battery management system includes a memory for storing data related to the operation of the battery, and the battery management system is also configured to communicate the data related to the operation of the battery to other processors for analysis.

In a cordless power tool system, protection methods, circuits and devices are provided to protect against fault conditions within a battery pack that is operatively attached to a power tool or charger, so as to prevent internal or external damage to the battery pack or attached tool or charger. The exemplary methods, circuits and devices address fault conditions such as over-charge, over-discharge, over-current, over-temperature, etc.

In an exemplary embodiment, a battery conditioning system monitors battery conditioning and includes a memory for storing data based thereon; for example, data may be stored representative of available battery capacity as measured during a deep discharge cycle. With a microprocessor monitoring battery operation of a portable unit, a measure of remaining battery capacity can be calculated and displayed. Where the microprocessor and battery conditioning system memory are permanently secured to the battery so as to receive operating power therefrom during storage and handling, the performance of a given battery in actual use can be accurately judged since the battery system can itself maintain a count of accumulated hours of use and other relevant parameters. In the case of a nonportable conditioning system, two-way communication may be established with a memory associated with the portable unit so that the portable unit can transmit to the conditioning system information concerning battery parameters (e.g. rated battery capacity) and / or battery usage (e.g. numbers of shallow discharge and recharge cycles), and after a conditioning operation, the conditioning system can transmit to the portable unit a measured value of battery capacity, for example. A battery pack having memory stores battery history and identifying data to be retrieved by a portable battery powered device. Battery status information may be utilized in conjunction with characteristic battery history data in order to optimize charging and discharging functions and to maximize the useful life of a battery pack.

Apparatus for a modular battery management system with interchangeable slave modules connected to each cell and including a master module controlling and managing the battery system. All the modules receive power through a transfer switch that selectively switches between an external source, an auxiliary source, and the battery. The modules are configured to connect to a cell of the battery for charging and monitoring the cell individually. Each module is electrically isolated from the other modules. The modules are autonomous and shut down the battery and disconnect the module when a critical parameter of the cell is reached. When the battery is in service and a cell parameter approaches the critical level, the master controller instructs the corresponding slave module to charge the cell using battery power. The master module initializes the slave modules to uniquely identify the modules.

The object is to reliably detect a ground fault of a solar battery. To detect a ground fault position to take an efficient measure against the ground fault, DC power input from a solar battery is converted into AC power and supplied to a system. In a system interconnection inverter (utility connected inverter) having non-insulated input and output, the input voltage of a converter circuit and / or the intermediate voltage between the converter circuit and an inverter circuit are varied to control the potential to ground at each portion of the solar battery to a value other than a value close to zero.

A method of conducting an operation including a battery. The battery includes a cell having a voltage. Power is transferable between the cell and the electrical device. A controller is operable to control a function of the battery pack. The controller is also operable with a voltage at least one of equal to and greater than an operating voltage threshold. The cell is operable to selectively supply voltage to the controller. The method includes the act of enabling the controller to operate when the voltage supplied by the cell is below the operating voltage threshold.

The portable solar energy system stores electrical energy generated by a solar panel, which is made of an array of photovoltaic cells, in a dc storage battery, and upon demand converts the dc voltage of the battery to an ac output suitable for supplying conventional electrical appliances. The battery is a sealed lead-acid type and may be an Absorbed Glass Mat (AGM) battery. The system includes an energy storage and converting unit, which houses the battery and a dc-to-ac inverter. The inverter converts the stored energy of the battery, supplied at a low dc voltage, into the ac voltage and current required for supplying conventional appliances. A charge controller manages the flow of current from the solar panel to optimize the state of charge of the battery and to maximize the useful life of the battery. Additional circuitry monitors the discharge level of the battery to limit deep discharging.

An electric power tool is powered by a plurality of battery packs connected in series. The electric power tool comprises a controller configured to receive signals outputted from the integrated circuits located in each of the battery packs. A first voltage level-shifter is disposed between the controller of the electric power tool and one of the integrated circuits of the battery packs. The first voltage level-shifter is configured to shift the voltage level of the signal outputted from the respective integrated circuit to the tool controller to an acceptable level for the controller.

An energy source isolation and protection circuit is provided for an electronic device, such as a patient-worn or patient-carried medical device. The isolation and protection circuit includes a supply voltage rail, a reference voltage rail, an electrical load coupled across the supply voltage rail and the reference voltage rail, and an energy source for supplying a voltage to the electrical load via the supply voltage rail and the reference voltage rail. The isolation and protection circuit also includes a voltage-controlled switch architecture that is configured to detach and electrically isolate the energy source from the electrical load (and from itself) in response to the voltage of the energy source falling below a threshold voltage. The voltage-controlled switch architecture is also designed to maintain the energy source in the detached and electrically isolated state in the absence of operating voltage provided by the energy source to the voltage-controlled switch architecture.

The present application is directed toward a method and system for conserving battery power in low power systems. According to one aspect of the invention, a battery with a low power processor is used to shut off the monitor circuit that determines the charge remaining on a battery. Periodically, the low power processor will wake-up and power on the monitor circuit to determine the remaining charge of the battery. According to another aspect of the invention, there is a safety override circuit. The safety override circuit is a fail-safe that allows charge to flow from the battery when there is a fault with the low power processor, for example if the low power processor fails to wake-up.

When a battery pack having an output voltage of 14.4 V that is connectable to an electric tool in a sliding manner is used as a power supply source for the electric tool that is connectable to a battery pack in an insertion manner and has a rated voltage of 12 V, the electric tool and the battery pack are connected to each other with an adaptor interposed therebetween. The adaptor has an FET that is switched at a predetermined duty of a predetermined frequency. The battery pack and the electric tool are connected or disconnected to or from each other by the switching operation, thereby dropping the output voltage of the battery pack. The voltage from the battery pack is detected. When the detected voltage is out of a predetermined value range, it is judged that the overcurrent or overdischarge has occurred. Then, the FET is turned off to stop the electric tool.

High frequency power supplied to the primary coil from the high frequency power supply is transferred to the secondary coil by magnetic induction, and secondary coil AC is rectified to charge the battery pack housed in the portable electronic equipment. The battery charger is provided with internal batteries that are charged by input power and supply power to the high frequency power supply, and with a charging circuit to charge the internal batteries. The external case is provided with storage space between its top plate and bottom plate, and internal batteries, which are rectangular batteries, and a planar primary coil wound in a spiral shape are disposed in that storage space. The battery charger charges the internal batteries with input power, and when no power is input, internal battery power is converted to high frequency power and supplied to the primary coil to charge the battery pack.

In a battery pack manager that manages series-connected rechargeable unit cells, a cell equalizer equalizes the cell voltages by individually discharging the unit cells according to deviations from reference voltages. An overcharge / overdischarge detector detects an overcharge and an overdischarge state of each unit cell. An inhibit circuit prevents the cell equalizer from discharging the unit cells when the overcharge / overdischarge detector is activated to reduce the cell voltage variability, which would otherwise occur as a result of interference from the overcharge / overdischarge detector, so that the overcharge / overdischarge states of all unit cells can be determined with precision. Connecting lines of the unit cells are monitored to detect a line-cut. The inhibit circuit further inhibits the cell equalizer when the connecting lines are being monitored to reduce the cell voltage variability, which would otherwise occur as a result of interference from the line-cut detection, so that false line-cut detection is avoided.

A power pack system for charging a set of isolated batteries is provided. In an illustrative embodiment of the invention, a single fuel cell, a single DC-DC converter and a single system controller device comprises the power-generation side of the power pack. A set of switches is used to connect the power-generation side of the Power pack to one of the isolated batteries in the power pack, thereby recharging that particular battery in the battery power pack set. A battery protection and powerpath control device communicates with the system controller to determine which switches are to be closed depending upon which battery requires recharging. During normal operation the switches will follow the direction from the system controller. If a fault is detected by the battery protection circuit, the protection circuit will take priority and turn off the appropriate switch(es).

A state estimation value indicating a battery state is successively calculated from time to time according to a battery model capable of dynamically estimating the internal state of the secondary battery by using an inspection value of a sensor group indicating the secondary battery behavior. By using the sate estimation value at each moment estimated by the battery model expression at each predetermined cycle, an I / O-enabled time is predicted when a predetermined power is continuously inputted (charged) or outputted (discharged) from the current moment. A load operation instruction of the secondary battery is set so as to avoid overcharge and over-discharge of the secondary battery according to the operation request to the load and by considering the predicted characteristics between input / output power and input / output-allowed time.

A method of conducting an operation including a battery. The battery includes a cell having a voltage. Power is transferable between the cell and the electrical device. A controller is operable to control a function of the battery pack. The controller is also operable with a voltage at least one of equal to and greater than an operating voltage threshold. The cell is operable to selectively supply voltage to the controller. The method includes the act of enabling the controller to operate when the voltage supplied by the cell is below the operating voltage threshold.

The method and system for managing power supplied from a charging circuit to a power source in an implantable medical device comprises the steps of and circuitry for: measuring the current drain of the medical device; measuring the elapsed time since the last full charge of a power source of the device; calculating the actual capacity of the power source (corrected for fade) based on the variable of current drain and the variable of elapsed time; calculating the operating time based on the variable of current drain and the variable of the actual capacity of the power source; measuring the voltage of the power source; signaling the medical device when the power source voltage has reached a certain low value which requires disconnection from the power source; disconnecting, during discharging, the power source from the medical device upon the power source reaching a certain low voltage in order to prevent deep discharging of the power source and subsequent damage; precisely limiting the charging voltage to the power source in order to prevent overcharging beyond safe limits; disconnecting, during charging, the power source from the charging circuit upon the power source reaching a certain high voltage in order to prevent overcharging of the power source and subsequent damage; sensing when the electromagnetic waves being transmitted by an RF transmitter / charger induce a voltage level above a certain value at an RF receiver of the implanted power management system; reconnecting power supply inputs of the medical device to the power source upon sensing this induced high voltage level; monitoring the temperature of the power source during charging and discharging; disconnecting the charging circuitry from the power source if the temperature of the power source raises above a certain level during charging; reconnecting the charging circuitry to the power source when the temperature of the power source drops below a certain low value during charging; disconnecting the implanted medical device from the power source if the temperature of the power source raises above a certain level during discharging; and, reconnecting the medical device to the power source when the temperature of the power source drops below a certain low value during discharging.

A protection circuit is provided for protecting a secondary battery from overcharging and excessive discharge current by a simple circuit. The protection circuit is provided with a connection terminal (T3) for connecting the secondary battery (6); a connection terminal (T1) for connecting a charging device for charging the secondary battery (6) and / or a load device driven by a discharge current from the secondary battery (6); a bimetal switch (SW1) that is provided between the connection terminals (T1, T3) and turned off in the case of exceeding a specified temperature set beforehand; a heater (R2) for heating the bimetal switch (SW1); and an integrated circuit (IC1) for turning the bimetal switch (SW1) off by causing the heater (R2) to generate heat if a voltage applied to the connection terminal (T3) by the secondary battery (6) exceeds a preset reference voltage.

A battery pack having a secondary battery is disclosed. The battery pack comprises at least one voltage converter; and switching means for switching an operation mode of the voltage converter to one of a charging mode and a discharging mode, in the charging mode, a charging voltage being output to the secondary battery, in the discharging mode, a voltage of the secondary battery being converted into a predetermined discharging voltage and the converted voltage being output.

The method of controlling battery current limiting controls maximum charging and discharging current values according to the state of charge of the battery. The method of controlling current limiting integrates battery charging and discharging current to compute a first state of charge, determines first charging and discharging current limit value candidates from that first state of charge, computes a second state of charge based on battery voltage, and determines second charging and discharging current limit value candidates from that second state of charge. Further, the method takes the smaller of the first and second charging and discharging current limit value candidates as the charging and discharging current limit values for charging and discharging the battery.

A battery system according to the present invention includes: a battery module comprising a plurality of cell groups connected in series, each comprising a plurality of cells connected in series; a plurality of integrated circuits provided to corresponding each cell group of the battery module, that perform detection of terminal voltages of the cells in the corresponding each cell group, and that also perform diagnosis; and a battery controller that, along with issuing commands to the plurality of integrated circuits, also receives results of detection and results of diagnosis by the plurality of integrated circuits; wherein the battery system comprises a writable non-volatile memory, and data is stored in the writable non-volatile memory specifying usage environment of the battery module, including a maximum voltage or a maximum current of the battery module and history data based upon operation history of the battery module.

An abnormal voltage detector apparatus is provided for an assembled battery including a plurality of battery blocks connected in series to each other. In the abnormal voltage detector apparatus, a detecting part detects whether or not each of the battery blocks is in a voltage abnormality state by comparing either one of a voltage of each battery block and each battery measuring voltage, that is a voltage lowered from the voltage of each battery block, with a predetermined reference voltage, generates each of abnormality detecting signals containing information about a detected result, calculates a time ratio of a time interval, for which the assembled battery is in a voltage abnormality state, to a predetermined time interval, based on the abnormality detecting signals, and detects a voltage abnormality of the assembled battery based on a calculated time ratio.

The method and system for managing power supplied from a charging circuit to a power source in an implantable medical device comprises the steps of and circuitry for: measuring the current drain of the medical device; measuring the elapsed time since the last full charge of a power source of the device; calculating the actual capacity of the power source (corrected for fade) based on the variable of current drain and the variable of elapsed time; calculating the operating time based on the variable of current drain and the variable of the actual capacity of the power source; measuring the voltage of the power source; signaling the medical device when the power source voltage has reached a certain low value which requires disconnection from the power source; disconnecting, during discharging, the power source from the medical device upon the power source reaching a certain low voltage in order to prevent deep discharging of the power source and subsequent damage; precisely limiting the charging voltage to the power source in order to prevent overcharging beyond safe limits; disconnecting, during charging, the power source from the charging circuit upon the power source reaching a certain high voltage in order to prevent overcharging of the power source and subsequent damage; sensing when the electromagnetic waves being transmitted by an RF transmitter / charger induce a voltage level above a certain value at an RF receiver of the implanted power management system; reconnecting power supply inputs of the medical device to the power source upon sensing this induced high voltage level; monitoring the temperature of the power source during charging and discharging; disconnecting the charging circuitry from the power source if the temperature of the power source raises above a certain level during charging; reconnecting the charging circuitry to the power source when the temperature of the power source drops below a certain low value during charging; disconnecting the implanted medical device from the power source if the temperature of the power source raises above a certain level during discharging; and, reconnecting the medical device to the power source when the temperature of the power source drops below a certain low value during discharging.

Lower order control devices control plural battery cells configuring plural battery modules. An input terminal of the low order control device in the highest potential, an output terminal of the low order control device in the lowest potential, and a high order control device are connected by isolating units, photocouplers. Diodes which prevent a discharge current of the battery cells in the battery modules are disposed between the output terminal of the low order control device and the battery cells in the battery module on the low potential side. Terminals related to input / output of a signal are electrically connected without isolating among the plural low order control devices.

A protection of battery system having battery cells Cell1˜Cell3, FET switches SW1, SW2 that are connected to the high-side path and control on / off state of the path, as well as fuse F1 for cutting said path, primary protection circuits 31˜34 that detect abnormalities in charging / discharging of the battery cells and turn the FET switches off, and secondary protecting controller 38 that detect abnormalities in charging / discharging of the battery cells and controls the operation of fuse F1. Secondary protecting controller 38 controls fuse F1 if there is no tendency to a decrease in abnormalities after a prescribed period of time after control of the FET switch.

Lower order control devices control plural battery cells configuring plural battery modules. An input terminal of the low order control device in the highest potential, an output terminal of the low order control device in the lowest potential, and a high order control device are connected by isolating units, photocouplers. Diodes which prevent a discharge current of the battery cells in the battery modules are disposed between the output terminal of the low order control device and the battery cells in the battery module on the low potential side. Terminals related to input / output of a signal are electrically connected without isolating among the plural low order control devices.