Abstract: Determining a state of charge (SOC) of a rechargeable battery includes using a first process to determine a first value for the SOC of the battery and using a second process to determine a second value for the SOC of the battery and deriving the SOC as a weighted average of the first value for the SOC and the second value for the SOC. During a charging cycle of the battery an input charge of the battery is determined from an input current flowing into the battery and a charging time. During a discharging cycle an output charge of the battery is determined from an output current flowing out of the battery, a discharging time and an actual capacity of the battery is the sum of the input charge over charging cycles minus the sum of the output charge over discharging cycles.

Abstract: Disclosed herein is a composition for use in a negative active material in a valve regulated lead-acid battery, including a carbon material having a BET surface area from 150 m2/g to 2000 m2/g and having a D90-value greater than 5 ?m with the amount of carbon material ranging from 0.1 wt % to 1.5 wt % based on the total weight of the composition. Also disclosed herein is a valve regulated lead-acid battery, including a positive plate, a negative plate, a separator, and an electrolyte disposed in a container with a valve, the negative plate including a substrate of lead or a lead alloy and a negative active material of a composition including a carbon material having a BET surface area from 150 m2/g to 2000 m2/g and having a D90-value greater than 5 ?m, the amount of carbon material ranging from 0.1 wt % to 1.5 wt % based on the total weight of the composition.

Abstract: Determining a state of charge (SOC) of a rechargeable battery includes using a first process to determine a first value for the SOC of the battery and using a second process to determine a second value for the SOC of the battery and deriving the SOC as a weighted average of the first value for the SOC and the second value for the SOC. During a charging cycle of the battery an input charge of the battery is determined from an input current flowing into the battery and a charging time. During a discharging cycle an output charge of the battery is determined from an output current flowing out of the battery, a discharging time and an actual capacity of the battery is the sum of the input charge over charging cycles minus the sum of the output charge over discharging cycles.

Abstract: Disclosed herein is a composition for use in a negative active material in a valve regulated lead-acid battery, comprising: a carbon material having a BET surface area from 150 m2/g to 2000 m2/g and having a D90-value greater than 5 ?m; wherein the amount of carbon material ranges from 0.1 wt % to 1.5 wt % based on the total weight of the composition. Also disclosed herein is valve regulated lead-acid battery, comprising: a positive plate, a negative plate, a separator, and an electrolyte disposed in a container comprising a valve, wherein the negative plate comprises a substrate comprising lead or a lead alloy and a negative active material comprised of a composition comprising a carbon material having a BET surface area from 150 m2/g to 2000 m2/g and having a D90-value greater than 5 ?m; wherein the amount of carbon material ranges from 0.1 wt % to 1.5 wt % based on the total weight of the composition.

Abstract: A plastic battery cover for closing a battery housing includes a top surface, a bottom surface, at least one terminal extending through the battery cover, and a connecting flank extending from the at least one terminal, the connecting flank in contact with the battery cover. The connecting flank is configured such that a region between the at least one terminal and the top surface of the battery cover is adapted to prevent the formation of a gap between the terminal and the adjacent portion of the battery cover after the volume reduction of the plastic in this region during the manufacture of the battery cover by injection molding.

Abstract: A plastic battery cover for closing a battery housing includes a top surface, a bottom surface, at least one terminal extending through the battery cover, and a connecting flank extending from the at least one terminal, the connecting flank in contact with the battery cover. The connecting flank is configured such that a region between the at least one terminal and the top surface of the battery cover is adapted to prevent the formation of a gap between the terminal and the adjacent portion of the battery cover after the volume reduction of the plastic in this region during the manufacture of the battery cover by injection molding.

Abstract: A process for the production of a lead accumulator comprising installing electrode plates and separators in a battery box, introducing an electrolyte in the form of a thixotropic gel including sulphuric acid and gel-forming agent into an electrolyte space and, closing of the battery box, wherein after installing the electrode plates the entire amount of sulphuric acid required for a desired electrolyte concentration is introduced into an electrolyte space within the box to form the electrode plates and after formation, an aqueous silica sol with 15 to 60% by weight of solids component, with a specific surface area of solids of 100 to 500 m.sup.2 /g, is added in such an amount that a solids concentration of the electrolyte, with respect to the overall weight thereof, of 3 to 20% by weight is obtained, and then the content of the electrolyte space is homogenously mixed.