4245results about "Battery disconnect circuits" patented technology

PCT No. PCT/NZ96/00060 Sec. 371 Date Dec. 22, 1997 Sec. 102(e) Date Dec. 22, 1997 PCT Filed Jun. 20, 1996 PCT Pub. No. WO97/01103 PCT Pub. Date Jan. 9, 1997A battery monitoring system includes a circuit for use with a battery which is one of a defined (quantified re volts supplied at known current loads at known discharge levels) type of battery such as the lead-acid batteries used in vehicles. Preferred embodiments monitor at least the battery voltage under load while measuring the drawn current and use stored numerical information in order to determine whether the battery has been discharged down to a predetermined limit; one which generally retains enough charge to perform a defined act such as starting an engine. If the battery is so depleted a non-critical load (e.g. accessories) is disconnected by a switch. Changes in the non-critical load are monitored and the non-critical load is reconnected for a predetermined period when a change is detected in order to start the engine.

A system and method for battery protection. In some aspects, a method of conducting an operation including a battery pack, includes the acts of monitoring a first battery pack condition at a first monitoring rate, determining when a second battery pack condition reaches a threshold, after the second battery pack condition reaches the threshold, monitoring the first battery pack condition at a second monitoring rate, the second monitoring rate being different than the first monitoring rate. In some aspects, a method of conducting an operation including a battery, the battery including a cell having a voltage, power being transferable between the cell and the electrical device, a controller operable to control a function of the battery pack, the controller being operable with a voltage at least one of equal to and greater than an operating voltage threshold, the cell being operable to selectively supply voltage to the controller, includes the act of enabling the controller to operate when the voltage supplied by the cell is below the operating voltage threshold.

A cordless power tool has a housing which includes a mechanism to couple with a removable battery pack. The battery pack includes one or more battery cells as well as a system to dissipate heat from the battery pack.

A two-wire smart load control device, such as an electronic switch, for controlling the power delivered from a power source to an electrical load comprises a relay for conducting a load current through the load and an in-line power supply coupled in series with the relay for generating a supply voltage across a capacitor when the relay is conductive. The power supply controls when the capacitor charges asynchronously with respect to the frequency of the source. The capacitor conducts the load current for at least a portion of a line cycle of the source when the relay is conductive. The load control device also comprises a bidirectional semiconductor switch, which is controlled to minimize the inrush current conducted through the relay. The bidirectional semiconductor switch is rendered conductive in response to an over-current condition in the capacitor of the power supply, and the relay is rendered non-conductive in response to an over-temperature condition in the power supply.

When detecting an abnormality in some storage batteries, the hybrid vehicle control system separates the faulty storage batteries and leads the sound storage batteries to a high SOC.

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.

A compact battery pack with high handling ability and restraining degradation of battery cells. The battery pack includes an insertion portion to be inserted into a handle portion of a cordless power tool and an accommodation portion in which all battery cells are accommodatable. A protection board with a protection circuit that protects batteries against overcharge and over-discharge is installed in the insertion portion. A switching element is connected between the battery cells and a drive motor of the power tool. An air passage in communication with the battery pack is formed within the handle and a main housing of the cordless power tool. The switching element is positioned at the air passage.

In a secondary battery protection circuit (200A) having a protection arrangement (210, 220, 230, 240, 250A) for protecting a secondary battery (300), by turning a discharge control switch (FET1) and a charge control switch (FET2) on and off, so as to prevent the secondary battery from overdischarging and overcharging, the secondary battery protection circuit further has a security arrangement (260, 270) for precluding counterfeit goods of a secondary pack. The security arrangement has an interface circuit (260) for interfacing to a portable unit body (500) and an authentication circuit (270) for calculating an identifier obtained by encrypting a random number received from the portable unit body to return the identifier to the portable unit body.

A battery state monitoring portion intermittently monitors the low voltage battery for supplying power to electrical components arranged in a vehicle while the power supply to the low voltage system load other than a +B load is stopped, a DCDC converter is stopped, and a +B power supply mode in which the vehicle cannot travel is set. A charging control portion starts up the DCDC converter and charges the low voltage battery with the power of a high voltage battery as a power source of the vehicle through the DCDC converter when the voltage of the low voltage battery becomes lower than or equal to a charging start voltage when the +B power supply mode is set. The present invention can be applied to a charging device of a battery of an electric vehicle.

The present invention provides a protection circuit disposed in a lithium-ion cell for protection of the lithium-ion cell. The protection circuit includes a first protection module, a second protection module, an integrated circuit module, a thermal sensor or thermocouple, a switch, a fuse and/or a resistor.

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 charging monitor has: a switch that is disposed between a load section having a storage battery and an external AC power supply supplying a current to the load section via a plurality of lines and interrupts the supply of the current from the external AC power supply to the load section; a current detection circuit that outputs a detection signal corresponding to a difference in level between currents flowing through the lines; a suppression circuit that suppresses a DC component contained in the detection signal; a filter circuit that filters a plurality of frequency components contained in the detection signal so that attenuation increases as a frequency becomes high; a rectifier smoothing circuit that rectifies and smoothens an output signal obtained when the detection signal passes through the filter circuit and the suppression circuit; and an electric leakage determination circuit that detects an electric leakage and shuts off the switch when the level of the signal smoothened by the rectifier smoothing circuit exceeds a preset reference level.

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 includes overcurrent limiting transistors and respective sensors in proximity to battery cell and the transistors. A CPU in the battery pack receives temperature signals from the sensors and selects an action to control temperature based on the temperature signals.

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.