Abstract: Nonintrusive sensors capable of measuring various storage cell parameters such as voltage, state-of-charge, electrolyte level, internal resistance, and temperature are attached to a monitoring module which gathers and processes signals representative of information concerning the condition of electrolytic storage cells and transmits the information to a central computer for further processing. In response to commands issued by the central computer, appropriate maintenance and/or repair operations can be initiated. Alternatively, the system described can be used to automatically perform such maintenance tasks as checking and adding electrolyte levels, reducing the voltage in cells whose output voltage is too high, and leveling the state-of-charge of each cell in an array of electrolytic storage cells. The system can monitor other functions of the electrolytic storage cells, including the evolution of hydrogen gas and the accumulation of sediments in individual electrolytic storage cells.

Abstract: An automatic monitoring system of storage batteries housed in battery rooms comprises an acquisition satellite associated with a sensor to measure various physical parameters representative of the operating state of a pilot battery cell, notably the density, temperature and electrolyte level, a data concentrator located outside the corresponding battery room and arranged to communicate by radioelectric waves with the acquisition satellite, and a centralized processing unit connected to the concentrator by a two-way cabled communication network.

Abstract: An apparatus for monitoring the state of charge of a battery having a shunt resistor connected in series with a battery and an integrating circuit connected across the terminals of the shunt resistor is provided. The integrating circuit includes a Memoriode having a large capacitance and the capability to store charge for long periods of time, so that the integration can be performed along the same curve even if power to the integrating circuit is interrupted.

Abstract: A specific gravity detecting apparatus for a lead-acid battery having two electrodes adapted to be immersed in an electrolyte to provide a potential difference therebetween which is indicative of the specific gravity of the electrolyte. One of the two electrodes is a lead electrode composed of a collector 6 made of lead and a lead alloy and a porous lead body 4 covered by an acid resistant porous sleeve 3; the other is a lead dioxide electrode composed of a collector 6' made of lead and a lead alloy and a porous lead dioxide body 5 covered by an acid- and oxidation-resistant porous sleeve 3'. The two electrodes are charged normally or as required while there is no necessity of obtaining specific gravity data, and later discharged with another lead electrode as an opposite electrode so that, in the open-circuit state, the potential difference between the lead electrode and the lead dioxide electrode is accurately determined.

Abstract: A battery cap indicator has a transparent cap which permits the viewer to read both electrolyte level and density simultaneously, the indicators also giving the viewer the ability to determine whether the readings are at the higher or lower end of an acceptable range. The float assemblies of the indicator are configured for minimum friction with the guiding structure of the indicator body.

Abstract: A method for rapidly testing rechargeable electrochemical cells following assembly which enables the testing of cells to be carried out in a substantially uncharged condition. Cells in the assembly line are energized with a constant current pulse applied to their electrodes via the cell terminals, the current being of sufficient magnitude and duration so as to develop an increased charge voltage between the cell terminals. The charge voltage so developed during the application of the current and while the electrodes of the cell are incompletely charged is then measured and compared with a predetermined zone of acceptable values for cell performance. Preferably, the developed charge voltage is permitted to stabilize prior to measurement. In addition, measurements of open circuit voltage are taken immediately before and after application of the current pulse.

Abstract: A gassing detector for use in modifying the charge rate in charging circuits for liquid electrolyte secondary cells. A light is reflected from the surface of the electrolyte into a photodetector. A discriminator circuit distinguishes the pulses in the photodetector output characteristic of the rippling caused by gassing of the cell and produces a signal to cause the charger to reduce the charge rate.

Abstract: A transducer and battery performance indicator which senses various levels of specific gravity and other conditions of a liquid or electrolyte of varying degrees of translucency and converts the measurements into electrical analog signals which are fed to an indicator read-out. The device may include temperature and level sensors, as well as an agitator for circulating electrolyte, and a number of them are used remotely to monitor a bank of batteries.

Abstract: Electrolyte from a battery cell is circulated by pump, through a container which contains a hydrometer float, and back to the cell. The float has an opaque neck which interrupts light passing from a light source assembly to a light receiving assembly, and the receiving assembly controls slave means, which can be an illuminated sign, as for example a group of visible light emitting diodes, the number of which illuminated indicating the density of the electrolyte. The slave means can alternatively be a volt meter, or a battery charger, the rate of charge of which is controlled by a voltage signal.