Abstract: A method for avoiding the spread of a thermal event in an enclosure containing several modules (1, 2, 3, 4) of electrochemical elements, said method comprising the following steps: —detecting one or more critical modules (1, 2, 3) situated in the enclosure, and affected by a thermal event (13), a module being critical when one or more parameters associated with the status of the module have reached or crossed a predetermined threshold, —spraying a coolant (12) onto, or into, the critical module or modules (1, 2, 3) for a determined duration and/or at a determined flow rate, one or more modules (4) not detected as being critical modules not receiving any coolant (12).

Abstract: An industrial type vented cell storage battery includes an electrode package including at least one positive electrode containing nickel hydroxide, one negative electrode, and one hydrophilic and gas-permeable separator an extension of which beyond said electrode package is in contact with the electrolyte contained in said space. It also includes an oxygen recombination device. It contains an excess quantity of alkaline electrolyte. A space between the base of the electrode package and the bottom of the container contains at least some of the excess quantity of electrolyte.

Abstract: An aqueous alkaline electrolyte Ni-MH sealed secondary storage cell includes a bundle of electrodes placed in a container and made up of a plurality of negative and positive electrodes. The space separating the negative electrode from the positive electrode contains a separator. The separator is permeable to gases and a recombination device is placed between two adjacent negative electrodes and has a wetting angle of at least 45°, an average pore section of at least 103 &mgr;m2, and a thickness from 0.2 mm to 5 mm.

Abstract: A sealed nickel-metal hydride storage cell comprises a positive electrode whose electrochemically reactive material is a hydroxide containing principally nickel and a negative electrode whose electrochemically active material is an intermetallic compound capable of forming a hydride when charged. The total quantity of electrochemically active material in the negative electrode exceeds the total quantity of electrochemically active material in the positive electrode so that the total negative capacity exceeds the total positive capacity by an amount of at least 15% referred to as the overcapacity. Part of the overcapacity, referred to as the precharge, is partly in the charged state when the positive electrode is completely discharged and the remaining part, referred to as the surplus, is in the discharged state when the positive electrode is completely charged. The precharge is less than 10% of the negative overcapacity.

Abstract: An aqueous alkaline electrolyte Ni-MH sealed secondary storage cell includes a bundle of electrodes placed in a container and made up of a plurality of negative and positive electrodes. The space separating the negative electrode from the positive electrode contains a separator. The separator is permeable to gases and a recombination device is placed between two adjacent negative electrodes and has a wetting angle of at least 45°, an average pore section of at least 103 &mgr;m2, and a thickness from 0.2 mm to 5 mm.

Abstract: A maintenance-free open industrial storage battery includes an electrode assembly comprising at least one positive electrode, one negative electrode, one separator disposed between the negative electrode and the positive electrode, an alkaline electrolyte covering the top end of the assembly before electrical cycling and a valve the relative operating pressure of which is less than 1 bar. The total capacity of the negative electrodes is greater than the total capacity of the positive electrodes. The separator is permeable to oxygen and the storage battery contains an oxygen recombination device such that after at least one cycle of charging and discharging the storage battery operates without loss of electrolyte at a charging current at least equal to Ic/10 where Ic is the current discharging the capacity of the storage battery in one hour.

Abstract: The present invention provides a method of controlling rapid charging of an alkaline-electrolyte industrial storage cell of the "maintenance-free" or "sealed" type, the cell possessing a nominal capacity Cn, a voltage U, and an internal temperature T, wherein charging is stopped at a percentage charge greater than 75% of Cn as follows:a voltage threshold Us is fixed which corresponds to the desired final percentage charge for said cell;the voltage U and the temperature T of said cell are measured;a corrected voltage Uc is calculated using the following formula:Uc=U-k(T-Tc)where voltages are expressed in volts, Tc is an arbitrarily-selected reference temperature, and k is a constant coefficient expressed in volts per temperature unit; andUc is compared with said voltage threshold Us, and charging is stopped when Uc is not less than Us.

Abstract: A method of charging an industrial maintenance-free Ni-MH storage cell, the method comprising in combination a first stage at a constant current I.sub.1 lying in the range I.sub.c /10 to I.sub.c /2, and a second stage at a constant current I.sub.2 lying in the range I.sub.c /50 to I.sub.c /10, the changeover from the first stage to the second stage taking place when the time derivative of the temperature reaches a threshold value which varies as a function of the temperature at the time of the changeover.

Abstract: A method of charging a sealed nickel-cadmium battery, in which the battery first is charged for a duration t.sub.1 at current I.sub.1, such that: I.sub.min .ltoreq.I.sub.1 .ltoreq.I.sub.max with 0.ltoreq.I.sub.min .ltoreq.C.sub.1 and 0.2 C.sub.1 .ltoreq.I.sub.max .ltoreq.5 C.sub.1, and I.sub.1 32 .alpha.C.sub.1 (1+aT) where 0.2.ltoreq..alpha..ltoreq.5 and 0.ltoreq..alpha..ltoreq.0.1, where T is the temperature and C.sub.1 is the nominal current. The battery then is charged at a voltage U.sub.2, such that: U.sub.min .ltoreq.U.sub.2 .ltoreq.U.sub.max where 1.45 V.ltoreq.U.sub.min .ltoreq.1.75 V and 1.50 V.ltoreq.U.sub.max .ltoreq.1.80 V, and U.sub.2 =U.sub.i +bT, and a duration t.sub.2 =.beta.t.sub.1 +c where 0.2.ltoreq..beta..ltoreq.5 and 5.ltoreq.c.ltoreq.60. Current I.sub.1 and voltages U.sub.1 and U.sub.2 are readjusted as the temperature in the battery changes. Apparatus for performing the inventive method also is provided.

Abstract: A separator for an alkaline storage cell comprises: two sheets of felt (10, 20) made of polypropylene, polyamide, or polyethylene, and having a thickness lying in the range 0.1 mm to 0.4 mm; and an intermediate sheet (4) that is plane, microporous, and made of a sintered material selected from polyvinyl chloride and polyethylene. The thickness of said microporous sheet lies in the range 0.1 mm to 0.4 mm; the diameter of its pores lies in the range 10 .mu.m to 100 .mu.m, and its weight lies in the range 100 g/cm.sup.2 to 400 g/cm.sup.2.

Abstract: A reduced maintenance, vented nickel-cadmium storage cell comprising a set of positive electrodes, a set of negative electrodes in which the active mass is consolidated by a polymer, and separators constituted by at least one felt made of a substance selected from a polyamide, polypropylene, polyethylene, individually or mixed together, and without an additional membrane. The inter-electrode distance is in the range 0.2 mm and 0.5 mm, the internal pressure is maintained in the range 0 bars to 0.7 bars, and the cell contains free electrolyte in such a manner as to present a charging characteristic when charging at constant voltage in the temperature range -30.degree. C. to +60.degree. C. that enables the end of charging to be detected because of the existence of a sudden rise in voltage.

Abstract: A vented nickel-cadmium storage cell with reduced water consumption has its inter-electrode gap occupied by a separator comprising at least one polymer fiber felt and a perforated polyolefin film.