Varta Batterie Aktiengesellschaft

Bernhard E Kallup

Klaus Salamon

Gerolf Richter

Christian Ressel

Christian Kubis

Wolfgang Glittenberg

In connection with a device for casting lead grids for electric battery plates, a highly porous ceramic mold lining, preferably of zirconium oxide, is prepared by flame-spraying. Such a lining can include a thin surface coating on a profiled, basic metallic mold or a separately prepared insert plate which is retained to a metallic mold molder. The ceramic surface coating may be accurately formed in place, or may be formed as an over-spray which is then reduced in thickess. Formation of the surface coating may be accomplished by placing masks on the basic metallic mold during the flame spraying, for those areas of the grid which tend to accumulate material, or by adjusting an initially coarse profile of the ceramic layer to the exact profile of the casting by a material-removing treatment. Alternatively, the insert plate may be manufactured on a matrix with a surface contour which corresponds to the half-profile of the lead grid, as a positive mold to which the ceramic material is applied by flame-spraying after an intermediate coating with a removable adhesive layer. The resulting ceramic coating is then subjected to surface grinding, and is removed from the matrix.

Process for manufacturing device for casting lead grids for electric

A device, configured as a double mold, for casting terminal bars (straps) and terminal poles onto the lugs of a completely assembled plate group for electric storage batteries ensures optimum attachment of all of the lugs (both polarities) to the molten bar lead if the heat exchange between the bar lead and the dipped volume of each negative or positive lug is identical. This requirement is met by causing the negative and positive casting molds, together with their contents, to form thermally equivalent sections or blocks, which are equalized if necessary, by changing the dimensions (thickness) of the mold's walls. When the lugs are made of lead or a lead alloy, such a double mold also makes it possible, during a subsequent two-stage cooling process, to first allow the terminal poles to solidify, simultaneously, and to then allow the terminal bars to solidify, simultaneously. If the negative plates of the cell group have copper grids and lugs (which may also be coated with lead or lead-tin alloys), the two-stage cooling process must be effected at different working rates for the two polarities.

Device for attaching terminal straps and terminal poles to the lugs of a

A casting mold for manufacturing grid plates for lead batteries makes use of easily interchangeable mold inserts for each half of a two-part, external metallic mold holder. The mold inserts are made of a highly porous microfiber nonwoven material, and render unnecessary the conventional cork-flour coating of casting molds due to good thermal insulating properties, high permeability to air and non-wettability by lead. The casting mold inserts are manufactured in a process which involves fixing of the nonwoven material with a curable binder either during or after shaping of the negative for the grid plate, so that the resulting parts assume a cardboard-like consistency.

Growing community of inventors

Aschaffenburg, Germany

Bernhard E Kallup