Abstract: A method of allocating power across a microgrid having a plurality of energy storage systems with different power and/or energy capacities, and different states of charge. The method includes allocating a total charge request and/or a total discharge request across the energy storage systems; and limiting the charge and/or discharge of one or more energy storage systems to a submaximal value.

Abstract: A shutdown method applicable to a terminal having a rechargeable battery, the method includes: determining a first impedance and a second impedance of the rechargeable battery, wherein the first impedance is an impedance determined based on a current temperature of the rechargeable battery, and the second impedance is an impedance determined based on a current number of charge times of the rechargeable battery; determining a target impedance as a larger impedance value from the first impedance and the second impedance; determining a shutdown voltage of the terminal based on a preset open circuit voltage of the rechargeable battery, the target impedance and a current operating current of a charging circuit; and controlling the terminal to shut down, when an operating voltage of the rechargeable battery is decreased to the shutdown voltage.

Abstract: The present disclosure relates to a device and method for controlling discharge by calculating a slope of a discharge profile of a battery having a lithium-based cathode material and a silicon-based anode cell material, counting a frequency the slope is equal to or smaller than a preset slope value and adjusting a final discharge voltage in response to the counted frequency being above a predetermined frequency.

Abstract: In a status detection system, a data acquisition circuit monitors statuses of a battery to generate status data. A storage medium stores a set of lookup tables. A lookup table of the lookup tables includes a set of datasets corresponding to a set of time frames. Each dataset includes digital values of parameters of the battery obtained in a corresponding time frame of the time frames. A controller receives the status data and updates the lookup tables based on the status data. The controller also obtains a current dataset of the parameters based on the status data, searches the lookup table for a previous dataset that matches the current dataset, compares a current value of a parameter in the current dataset with a previous value of the parameter in the previous dataset, and determines whether a potential fault is present in the battery based on a result of the comparison.

Abstract: An installation for recharging an energy storage means, such as a battery of an electric vehicle, by conduction of energy from an electric power source to the energy storage means, where the battery is electrically connected to an on-board device and provided with a plurality of electric contacts, and on the ground, a ground device, combined with the on-board device, is connected to the electric power source and includes a plurality of electric contacts, each electric contact of the ground device being able to be put into contact with a corresponding contact of the on-board device, and the installation being able to safely apply an electric recharging power issued by the electric power source to the battery, where the plurality of electric contacts of the on-board device and of the ground device exclusively includes a phase contact and neutral contact.

Abstract: A method for detecting failure of a battery cell due to an unknown discharge current, including connecting a detector in series between the battery cell and a power supply for supplying a charging power, determining whether the charging of the battery cell progresses by the charging power in excess of a predetermined battery cell specific charging reference time, measuring a current value of the battery cell in real time if the charging of the battery cell progresses in excess of the battery cell specific charging reference time, determining whether the current value of the battery cell measured in real time exceeds a predetermined battery cell specific failure determination reference current range value, and determining a state of the battery cell as a failure state if the current value of the battery cell exceeds the predetermined battery cell specific failure determination reference current range value.

Abstract: This disclosure describes a configuration of an unmanned aerial vehicle (UAV) that will facilitate extended flight duration. The UAV may have any number of lifting motors. For example, the UAV may include four lifting motors (also known as a quad-copter), eight lifting motors (octo-copter), etc. Likewise, to improve the efficiency of horizontal flight, the UAV also includes a pushing motor and propeller assembly that is oriented at approximately ninety degrees to one or more of the lifting motors. When the UAV is moving horizontally, the pushing motor may be engaged and the pushing propeller will aid in the horizontal propulsion of the UAV.

Abstract: Power line carriers (PLCs) are susceptible to transients and electromagnetic interference (EMI) on the power line. To address transients and EMI on the power line, an improved power PLC involves transmitting a signal over the power line using a controlled current source, where the current source is modulated by the signal. The current source output is designed to be independent of the voltage on the power line and the load, and thus, is less susceptible to transients and EMI on the power line. The system architecture of the improved PLC also allows for simple, predictable, and flexible termination. In an example implementation in the automotive industry, the improved high frequency PLC may provide a low cost replacement for existing communication interfaces. The improved PLC may consolidate system in-vehicle communication, reduce in-vehicle wiring, provide system flexibility, and decrease vehicle weight and system cost.

Abstract: A battery charging method, including obtaining a voltage capacity ratio for a reference charge C-rate and voltage capacity ratios for N (N an integer of 1 or more) charge C-rates greater than the reference charge C-rate, each of the voltage capacity ratios for the reference charge C-rate and the N charge C-rates being defined as a ratio of a voltage variance to a capacity variance depending on a change in state of charge (SOC) of a battery when the battery is charged at a corresponding one of the C-rates, comparing the voltage capacity ratio of the reference charge C-rate with each of the voltage capacity ratios of the N charge C-rates, and then setting a charge C-rate of the N charge C-rates so that a difference in voltage capacity ratio is minimized for each of SOC sections, and charging the battery with the charge C-rates corresponding to the SOC sections.

Abstract: Provided are methods, systems and devices for thermodynamically evaluating electrochemical systems and components thereof, including electrochemical cells such as batteries. The present systems and methods are capable of monitoring selected electrochemical cell conditions, such as temperature, open circuit voltage and/or composition, and carrying out measurements of a number of cell parameters, including open circuit voltage, time and temperature, with accuracies large enough to allow for precise determination of thermodynamic state functions and materials properties relating to the composition, phase, states of charge, health and safety and electrochemical properties of electrodes and electrolytes in an electrochemical cell. Thermodynamic measurement systems of the present invention are highly versatile and provide information for predicting a wide range of performance attributes for virtually any electrochemical system having an electrode pair.

Abstract: System and methods for estimating a capacity of a battery are presented. A measure of data skewness may be calculated from a battery system terminal voltage measurement. Inflection points in the data skewness of the terminal voltage measurement may align with transition points associated with a battery system. These transitions points may be associated with known SOCs determined from testing and/or characterization of the battery system. Using the detected transitions and associated SOCs and an indication of an accumulated charge provided to/from the battery between the transitions, an estimated capacity of the battery system may be determined.

Abstract: Hybrid and electric vehicles include a traction battery including many interconnected cells. Effective battery control, such as cell balancing, may rely on an accurate state of charge value for each of the cells. A method to reduce the computational effort of the state of charge calculation is developed. An accurate pack level state of charge calculation is implemented and represents the average cell state of charge. An average cell voltage is based on a pack voltage measurement. A state of charge difference is calculated for each cell based on a difference between a cell voltage and the average cell voltage. The state of charge difference utilizes the pack state of charge and a characteristic voltage and state of charge relationship for the cell. The cell state of charge is the sum of the pack state of charge and the state of charge difference.

Abstract: Systems and methods for balancing battery cells of a battery pack are disclosed. In one example, a charge imbalance is determined while battery cells operate in a high charge resolution voltage range. The charge imbalance determined during operation in the high charge resolution voltage range may be removed when the battery cells are operated in a low charge resolution voltage range. The system and method may be particularly useful for balancing battery cells that operate in the low charge resolution voltage range for a large portion of their operating time.

Abstract: A charger system with a digital interface circuit, wherein the digital interface circuit has an N-bit control register, wherein N is a positive integer no less than 2, and wherein the N-bit register has a primary state machine, at a first portion of addresses of the control register, configured to instruct operation statuses of a system management bus host; and a secondary state machine, at a second portion of addresses of the control register, configured to instruct a data bit of transmission of a corresponding control instruction under each of the operation statuses of the system management bus host.

Abstract: There is provided an electronic apparatus that can properly control a power state of an electronic apparatus by using a temperature of a battery pack. The electronic apparatus detects a temperature of a battery pack and a remaining capacity of the battery pack. If the temperature of the battery pack is less than or equal to a predetermined temperature, the electronic apparatus performs process for turning a power state of the electronic apparatus from ON to OFF based on the remaining capacity of the battery pack.

Abstract: A method for estimating charge capacity of a lithium iron-phosphate battery pack using data from a plug-in charge event. A laboratory-measured battery pack resistance, which is known to remain constant over a battery pack's life, can be used to determine open circuit voltage from terminal voltage during charging. Actual open circuit voltage after charging can be measured later, after the battery pack has rested for a sufficient amount of time. The two values of open circuit voltage, if taken at points on the battery pack's SOC-OCV curve which have great enough slope, provide two values of battery pack state of charge. By integrating charging current over the time interval between the two open circuit voltage readings, and using the two state of charge values, the battery pack capacity can be determined from the plug-in charge data.

Abstract: A bootstrap circuit includes: a charging voltage source; a charging diode, having an anode coupled to the charging voltage source; a high-voltage transistor, having a control terminal defined as a first connecting node and a channel coupled between a cathode of the charging diode and a bootstrap capacitor; a logic control circuit, having a first and a second logic outputs, and a logic input for receiving a charging command; a high-voltage control transistor, having a control terminal defined as a second connecting node and a channel coupled between charging voltage source and the first connecting node; a cut-off resistor, coupled between the first and the second connecting nodes; a charging control transistor, having a channel coupled between the second connecting node and a ground terminal, and a control terminal coupled to the second logic output; a control capacitor, coupled between the first connecting node and the first logic output.

Abstract: The present disclosure provides a solar cell pack and a method for balancing currents of solar cell modules. The solar cell pack includes a first solar cell module, a second solar cell module, a first balancer, a sampler and a controller. A negative pole of the first solar cell module is electrically connected to a positive pole of the second solar cell module. The first balancer is electrically connected to the first and the second solar cell modules in order to balance the current flowing through the both solar cell modules. An input terminal of the sampler is electrically connected to the first and the second solar cell modules. An output terminal of the sampler is electrically connected to an input terminal of the control unit. An output terminal of the control unit is electrically connected to an input terminal of the first balancer.

Abstract: Disclosed are an electric vehicle (EV), an EV charging stand, and a communication system therebetween, the EV including a charge control unit configured to detect a preparation state for charging a battery and output a resistance varying signal according to the detected state, and a resistor unit configured to vary a resistance value in response to the resistance varying signal, thus changing a voltage value of a state signal transmitted to the EV charging stand, and the EV charging stand including a comparator configured to receive a stage signal from the EV, compare a voltage value of the received state signal with a reference value, and output a signal in response to a result of comparing, and a control unit configured to receive the signal from the comparator and detect a preparation state for charging the battery of the EV.

Abstract: The method for charging or discharging a battery comprises measurement of the voltage at the terminals of the battery and comparison of the measured voltage with an end of charging or discharging voltage threshold. The method also comprises measurement of a temperature representative of the temperature of the battery and measurement of the current flowing in the battery to form a pair of measurements. The voltage threshold is then determined according to the pair of measurements. Charging or discharging of the battery is stopped when the voltage threshold is reached.

Abstract: The present invention discloses a charge control circuit for supplying power from an external power source to a first common node and charging a second common node from the first common node. A regulator circuit is coupled between the external power source and the first common node, and a transistor is coupled between the first common node and the second common node. The present invention detects an operation parameter of the transistor and controls an internal voltage source to generate a non-predetermined voltage difference accordingly. When the sum of the voltage at the second common node and the non-predetermined voltage is equal to or higher than the reference voltage, the voltage at the first common node is regulated to a level higher than the voltage at the second common node, and the transistor is in an optimum conductive state.

Abstract: The present invention relates to a drive system with energy recovery for driving a machine, in particular for driving a crane, wherein the drive system includes at least one fuel cell unit, at least one capacitive energy storage unit and at least one drive motor, and wherein the fuel cell unit and the energy storage unit are connected in parallel and feed at least one drive motor. According to the invention, the capacitive energy storage unit is dimensioned such that the differential voltage occurring during operation between the fuel cell unit and the capacitive energy storage unit is minimized to such an extent that the current caused by the voltage within the parallel connection of fuel cell unit and energy storage unit does not exceed a defined safe limit value, wherein the fuel cell unit and the energy storage unit are directly coupled with each other and with the remaining drive components without DC/DC converter.

Abstract: Techniques are described herein that are capable of increasing efficiency of wireless power transfer. A wireless power transfer system includes features that allow the system to be deployed in public spaces such as airports or in commercial establishments such as restaurants or hotels to allow a user to recharge one or more portable electronic devices while away from home. To accommodate wireless recharging of a variety of device types and states, the system may receive parameters and/or state information associated with a portable electronic device to be recharged and may control the wireless power transfer in accordance with such parameters and/or state information. For instance, the system may increase efficiency of the wireless power transfer based on such parameters and/or state information. The system may also provide a secure and efficient means for obtaining required payment information from the user prior to the wireless power transfer, thereby facilitating fee-based recharging.

Abstract: A charge control circuit includes a charge control unit that controls an operation of a charging unit that charges a rechargeable battery; and a voltage detection unit that detects a terminal voltage of the rechargeable battery, wherein when a terminal voltage of the rechargeable battery as detected by the voltage detection unit is lower than a predetermined first threshold-value voltage, being lower than a full-charge voltage which is a terminal voltage of the rechargeable battery in full charge, the charge control unit causes a constant current charging to the rechargeable battery by requesting the charging unit to supply a charging current of a predetermined first current value, causing the charging unit to supply a charging current of the first current value to the rechargeable battery, when the terminal voltage of the rechargeable battery as detected by the voltage detection unit exceeds the first threshold-value voltage but is less than the full charge voltage, the charge control unit causes the constan

Abstract: An electric storage device monitor includes a measurement unit detecting and obtaining a detected value, a power supply switch portion switching a power supply state of the monitor between a monitoring state and a low power consumption state, a wakeup timer to which an actuation time is set and starting counting time in response to switching to the low power consumption state and continuing counting time and outputting an actuation signal if reaching the actuation time, and a control unit. The switch portion switches from the low power consumption state to the monitoring state every time the wakeup timer outputs the actuation signal. The control unit controls the measurement unit to detect and obtain the detected value in the monitoring state, compares the detected value and a reference value, and changes the actuation time according to a comparison result of the detected value and the reference value.

Abstract: Some embodiments of the present invention provide a system that adaptively charges a battery, wherein the battery is a lithium-ion battery which includes a transport-limiting electrode governed by diffusion, an electrolyte separator and a non-transport-limiting electrode. During operation, the system determines a lithium surface concentration at an interface between the transport-limiting electrode and the electrolyte separator based on a diffusion time for lithium in the transport-limiting electrode. Next, the system calculates a charging current or a charging voltage for the battery based on the determined lithium surface concentration. Finally, the system applies the charging current or the charging voltage to the battery.

Abstract: A method for a rechargeable battery is disclosed that includes applying a charge voltage to the rechargeable battery; monitoring a battery voltage and a battery current of the rechargeable battery; and identifying a top of charge condition when for a defined time period the battery voltage is within a voltage tolerance of the charge voltage and the battery current is within a current tolerance of a threshold current. Also disclosed is a rechargeable battery system.

Abstract: Disclosed is a mobile device comprising a voltage supervisor and reset (VSAR) module configured to detect an input voltage, start a timer set to a predetermined time period responsive to detecting the input voltage, and output a low signal responsive to detecting the input voltage. The mobile device also comprises a battery charger module configured to receive the input voltage, receive the low signal, output a power signal, and charge a battery. The mobile device also comprises a processing module configured to receive the power signal, and attempt enumeration responsive to receiving the power signal, wherein the VSAR module is further configured to output a high signal to the battery charger module when the timer expires and enumeration has not been completed.

Abstract: A protection circuit module (PCM) for a secondary battery including a bare cell is provided. The PCM includes: a flexible printed circuit board (FPCB); and control circuitry mounted on the FPCB via adhesive material and configured for electrical coupling to the bare cell through the FPCB. The control circuitry is adapted to control charging and discharging of the bare cell.

Abstract: A battery charging circuit comprising: a semiconductor switch having an output connected to a rechargeable battery; a battery charge controller for receiving power from an external source, and supplying output power to a portable device and the input of the semiconductor switch, the current output of the battery charge controller being controllable; and a voltage sensing circuit for: measuring the voltage drop across the battery charge controller; and responding to the voltage drop across the battery charge controller by modulating the semiconductor switch to reduce the quantity of current supplied to the rechargeable battery when the voltage drop is too great; whereby the total power dissipated by the battery charge controller is controlled, the portable device receiving the power it needs to operate and the rechargeable battery receiving any additional available power.

Abstract: A method of evaluating battery packs is described. The method includes measuring a cell open voltage for each battery cell group in a section of battery cells; measuring a voltage under charge, or a voltage under load, or both, at a predetermined time interval for each battery cell group in the section of battery cells; determining the magnitude of the difference between the open cell voltage and the voltage under charge, or the voltage under load, or both, for each battery cell group in the section of battery cells by subtracting the voltage under charge from the cell open voltage, or subtracting the voltage under load from the cell open voltage, or both; and determining if the magnitude of the difference between the open cell voltage and the voltage under charge, or the voltage under load, or both, for each battery cell group in the section of battery cells exceeds a predetermined level.

Abstract: A circuit includes multiple battery modules and protection circuits respectively coupled to the battery modules. Each protection circuit includes a controller and a shunt circuit. The controller is coupled to one of the battery modules and detects a fault associated with the battery module. The shunt circuit is coupled to the battery module and the controller, and shunts a current around the battery module if the fault associated with the battery module is detected by the controller.

Abstract: An SOC of each battery cell is periodically detected, and an SOCmin and an SOCmax are determined. Battery cells having the SOCs larger than SOCmin+? are selectively discharged. After an elapse of a preset equalization processing time period, discharge of all the battery cells is stopped. The equalization processing time period is set based on a rate of change in the SOC of the battery cell subjected to discharge and a rate of change in the SOC of the battery cell not subjected to discharge such that a magnitude relationship between the SOC of the battery cell having the SOCmin and the SOC of another battery cell is not reversed.

Abstract: A method and a device are provided for determining the start of a charging process for an energy storage device in a vehicle, such as an electric vehicle. The method includes, but is not limited to determining at least one first parameter that indicates that a passenger is about to exit the electric vehicle. In addition, a first time t1 at which the charging process concludes at the earliest is determined, and a second time t2 at which the charging process is to have concluded at the latest is set, where t2?t1. Further, a determination is made as to whether a third time t3 at which a lowered second energy rate relative to the first energy rate is present before the second time t2 has been reached, and the start of the charging process is set in such a way that the at least one third time t3 lies within the charging process, and the charging process concludes by the second time t2 at the latest.

Abstract: In a voltage monitor, an abnormality detecting unit receives first information outputted from a first obtaining unit and second information outputted from a second obtaining unit, and determines that an abnormality that affects on at least one of first and second diagnostic thresholds arises in the voltage monitor when the first information is different from the second information. The abnormality detecting unit receives a first forced signal outputted from a first forced-output unit and a second forced signal outputted from a second forced-output unit. The abnormality detecting unit determines whether a timing at which the level of the first diagnostic threshold is switched for each step is deviated from a timing at which the level of the second diagnostic threshold is switched for a corresponding step based on a result of a comparison between the first forced signal and the second forced signal.

Abstract: An automated power reporting system is provided in one aspect. The system includes one or more devices that can report or transmit power status information over a bus or network. A protocol component utilizes a generalized protocol to process or convert the power status information over the network in order to facilitate power management operations for a plurality of devices. In this manner, devices that send power information can interact and exploit personal computing resources in order to better help users manage limited power resources for their respective devices.

Abstract: An apparatus is provided for an electronic device. The apparatus includes a dynamic electrical load, a secondary power coil receiver module that inductively receives a current from a primary coil of an power conversion system, a means for monitoring a current in the secondary receiver module being delivered to the dynamic load, a means for transmitting a power control signal to the power conversion system through the secondary charging coil, a current monitoring circuit that measures a current delivered to the dynamic load and a current limiter circuit that limits the current to the dynamic load based upon the measured charging current.

Abstract: Techniques are described herein that are capable of increasing efficiency of wireless power transfer. A wireless power transfer system includes features that allow the system to be deployed in public spaces such as airports or in commercial establishments such as restaurants or hotels to allow a user to recharge one or more portable electronic devices while away from home. To accommodate wireless recharging of a variety of device types and states, the system may receive parameters and/or state information associated with a portable electronic device to be recharged and may control the wireless power transfer in accordance with such parameters and/or state information. For instance, the system may increase efficiency of the wireless power transfer based on such parameters and/or state information. The system may also provide a secure and efficient means for obtaining required payment information from the user prior to the wireless power transfer, thereby facilitating fee-based recharging.

Abstract: A method and a charging device serve for charging rechargeable lithium accumulators. A charging current is injected into the accumulator, and the voltage is monitored on the accumulator during the injection process. Additionally, the variation in time of at least one state variable characteristic of the accumulator is monitored and injection of the charging current into the accumulator is continued until the variation in time of the state variable exceeds a predefined limit value.

Abstract: This invention discloses a method of performance analysis for VRLA battery which applies the method of using the float voltage dispersion ratio of the battery to evaluate the battery performance from a new perspective, and it is an online real-time test which applies several ways to evaluate the performance of the VRLA battery. According to the relevance between the dispersion of the float charge voltage of the battery and its performance, the method gets the result of the battery performance through calculating the battery float charge voltage dispersion ratio and making it relevant with the battery performance. It has small workload, convenient operation and no danger to the system when doing online testing. It also won't affect the cycle life of the VRLA battery.

Abstract: An apparatus estimates SOH of a battery based on a battery voltage variation pattern. A data storing unit obtains and stores battery voltage, current and temperature data from sensors, at each SOH estimation. A first SOC estimating unit estimates first SOC by current integration using the battery current data. A second SOC estimating unit estimates open-circuit voltage from the voltage variation pattern, and calculates and stores second SOC corresponding to the open-circuit voltage and temperature using correlations between the open-circuit voltage/temperature and SOC. A weighted mean convergence calculating unit calculates and stores convergence value for weighted mean value of ratio of the second SOC variation to the first SOC variation. A SOH estimating unit estimates capacity corresponding to the weighted mean convergence value using correlation between the weighted mean convergence value and the capacity, estimates relative ratio of the estimated capacity to an initial capacity, and stores it as SOH.

Abstract: An input/output control device for a secondary battery mounted on a vehicle includes a current estimating unit estimating a battery current input to or output from the secondary battery based on an input/output power of the secondary battery and outputting an estimated value (estimated current (Is)), a current sensor measuring the battery current and outputting a measured value (measured current (It)), and an input/output control unit controlling the input/output power based on the estimated value and the measured value. The input/output control device controls the input/output of the secondary battery, using the measured current (It) as well as the estimated value (Is), and therefore can suppress more reliably significant increase in heating value of the secondary battery and its peripheral parts.

Abstract: The present invention is directed at a method of handling a device charging state for a Universal Serial Bus (USB) connected mobile electronic device comprising the steps of sensing a presence of a bus voltage; sensing an enumeration acknowledgement signal between the device and a USB host; and transmitting a signal to instruct the device to enter the device charging state.

Abstract: In a hybrid vehicle equipped with an engine, a planetary gear mechanism linked to the output shaft of the engine and to a driveshaft, a first motor linked the planetary gear, a second motor inputting and outputting power to and from the driveshaft, and a battery inputting and outputting electric power to and from the motors, when the battery temperature Tb is lower than the preset reference temperature Tbref, drive control prohibits the intermittent operation of the engine and controls the engine and the motors to output the torque demand to the driveshaft with warm-up control of the battery. When the battery temperature Tb is higher than or equal to the preset reference temperature Tbref and the cooling water temperature Tw is higher than or equal to the preset reference temperature Twref, drive control performs the intermittent operation of the engine and controls the engine and the motors to output the torque demand to the driveshaft.

Abstract: A hybrid vehicle equipped with an engine, a planetary gear mechanism linked to the output shaft of the engine and to a driveshaft, a first motor linked to the planetary gear, a second motor inputting and outputting power to and from the driveshaft, and a battery inputting and outputting electric power to and from the motors. When a cooling water temperature Tw of the engine is lower than a threshold Twref, the intermittent operation of the engine is prohibited, and a controller performs a warm-up control on a condition that a battery temperature Tb is a preset reference temperature T?, while performing a low state of charge control on condition that a battery temperature Tb is higher than or equal to a preset reference temperature T? and lower than a preset reference temperature T?.

Abstract: The present invention relates to a method of charging a battery having internal resistance, the method including the step of feeding the battery with substantially constant charging current at a charging voltage that is regulated so as to compensate at least in part for the voltage drop generated by the internal resistance of the battery. The invention also provides a charger and a battery for implementing the method.

Abstract: The rechargeable battery abnormality detection apparatus is provided with an internal short circuit detection section (20b) that monitors rechargeable battery (1) voltage change when no charging or discharging takes place, and detects internal short circuit abnormality when battery voltage drop during a predetermined time period exceeds a preset threshold voltage; a degradation appraisal section (20d) that judges the degree of rechargeable battery degradation; and a threshold control section (20c) that incrementally increases the threshold voltage according to the degree of degradation determined by the degradation appraisal section (20d).

Abstract: An apparatus and method for improving use efficiencies of lead-acid batteries, and more particularly to 12V external lead-acid batteries used in vehicles of all types, load-leveling installations, and backup power applications. A method includes the steps of: a) determining a state of charge (SOC) for a lead-acid battery; b) comparing the SOC against a predetermined charge zone, the charge zone having an upper bound no more than about 90% maximum charge and more preferably no more than about 85% maximum charge and the charge zone having a lower bound no less than about 70% maximum charge and more preferably no less than about 75% maximum charge; and c) maintaining a charge of the lead-acid battery wherein the SOC is within the charge zone.

Abstract: A charger for a lithium ion secondary battery includes a series circuit of a reverse-current preventive switch, a charging switch and a current-detecting resistor, connected between the battery and the ground a charging control circuit controlling the reverse-current preventive switch and the charging switch, so as to make the battery repeat charging and opening at regular intervals, and so as to detect voltage difference between the specified voltage and the open circuit voltage of the battery during the opening; and a constant-current/constant-voltage control circuit commanding constant-current charging at a first set voltage set relatively high in a range not exceeding the upper limit voltage of the battery, so far as the voltage difference does not exceed a predetermined change-over voltage difference, and commanding constant-voltage charging at a second set voltage, which is lowered from the first set voltage, when the voltage difference becomes smaller than the change-over voltage difference.

Abstract: The management method comprises a charging phase and may comprise an optional prior phase of estimating the state of charge of the battery. Comparison of the absolute value of the slope of the voltage at the battery terminals with a full-charge threshold at the end of each period, when a pulsed current is applied, is used as end-of-charging criterion in the charging phase and/or as full-charge criterion in the phase of estimating the state of charge. The charging phase by pulsed current is interrupted when the slope reaches the full-charge threshold. This same comparison constitutes the criterion for estimating the necessity for going to a charging step after the prior phase of estimating the state of charge of the battery.