JP2012119175A - Electrode collector, electrode for lead-acid battery and lead-acid battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a lead mass without deteriorating mechanical strength and stiffness of an electrode collector.SOLUTION: An electrode collector 1 comprising lead or a lead alloy includes: an inner frame 11 in which an electrode active material 2 is provided and which forms a grid shape; and an outer frame 12 provided at an outside of the inner frame 11. A recessed portion 121 is formed on an outside peripheral surface 12a of the outer frame 12.

Description

  The present invention relates to an electrode current collector, a lead storage battery electrode using the same, and a lead storage battery.

  In the conventional lead storage battery, the reduction of the manufacturing cost is one problem. And as a method of reducing this manufacturing cost, it can be considered to reduce the amount of lead or lead alloy used in the lead storage battery.

  Here, most of lead or lead alloys used for lead-acid batteries are composed of an electrode current collector that constitutes an electrode, an electrode active material held by the electrode current collector, a plurality of positive electrode current collectors, and a negative electrode current collector. Each of them is included in a strap that is integrally connected, a pole column connected to the strap, and a terminal connected to the pole column.

  Since the electrode active material is a main part that determines the performance of the lead-acid battery, it cannot be easily reduced in weight. In addition, the strap, the pole column, and the terminal are usually designed to such an extent that they do not melt or deteriorate when a maximum charge / discharge current flows, and they cannot be easily reduced in weight.

  For this reason, it is conceivable to reduce the weight of the electrode current collector. However, the planar shape and thickness of the electrode current collector are matters determined by the design specifications for the amount of the electrode active material retained.

  Even in this situation, as a method of reducing the mass of the electrode current collector, the width of the outer frame generally referred to as the main bone, main rail, etc. provided outside the grid-shaped inner frame of the electrode current collector Alternatively, a method of reducing lead or lead alloy by reducing the thickness dimension is conceivable.

  However, if the width or thickness of the outer frame is reduced, there is a problem that the mechanical strength and rigidity of the electrode current collector are impaired. Moreover, if the thickness dimension of the outer frame is reduced, the entire electrode plate is thinned, resulting in problems such as the amount of electrode active material retained that does not satisfy the design specifications.

JP-A-10-308223

  Therefore, the present invention has been made to solve the above problems all at once, and its main intended task is to reduce the lead mass without impairing the mechanical strength and rigidity of the electrode current collector. Is.

  That is, the electrode current collector according to the present invention is an electrode current collector made of lead or a lead alloy, and includes an inner frame that forms a lattice in which an electrode active material is provided, and an outer frame that is provided outside the inner frame. And a recess is formed on the outer surface of the outer frame.

  If it is such, since the recessed part is formed in the outer surface of an outer frame, the lead mass of an outer frame can be reduced, without impairing the mechanical strength and rigidity of an outer frame. Thereby, the lead mass can be reduced without impairing the mechanical strength and rigidity of the entire electrode current collector. When the entire electrode current collector has mechanical strength and rigidity, it is possible to reduce the deflection due to its own weight when the electrode is held at both ends, and it is easy to handle in the electrode manufacturing process. be able to.

  In terms of the lead mass, in both the positive electrode current collector and the negative electrode current collector, the lead mass can be reduced by providing a recess on the outer surface of the outer frame. However, since the positive electrode current collector is a portion that becomes corroded by charging and becomes a main life factor of the lead-acid battery, it is conceivable that when the positive electrode current collector is reduced in weight, the life performance is lowered. Therefore, in the negative electrode current collector that hardly deteriorates as compared with the positive electrode current collector, by providing a recess on the outer surface of the outer frame, the life of the lead storage battery is shortened, or the negative electrode current collector The lead mass can be reduced without impairing the mechanical strength.

  In order to reduce the lead mass of the electrode current collector as much as possible, it is desirable that the recess is formed on substantially the entire outer surface of the outer frame. Here, the concave portion is formed over substantially the entire outer surface. In other words, the concave portion forming one line is formed over substantially the whole, that is, the concave groove is formed over substantially the entire outer surface. This is a concept including that a plurality of recesses are discretely formed, for example, at substantially equal intervals.

  An electrode for a lead storage battery according to the present invention includes an electrode current collector having a grid-like inner frame on which an electrode active material is provided and an outer frame provided on the outer side of the inner frame. And an electrode active material provided on the frame, and a recess is formed on the outer surface of the outer frame.

  Furthermore, the lead storage battery according to the present invention includes a positive electrode plate made of a positive electrode active material and a positive electrode current collector, a negative electrode plate made of a negative electrode active material and a negative electrode current collector, and an electrolytic solution in which the positive electrode plate and the negative electrode plate are immersed. And at least one of the positive electrode current collector or the negative electrode current collector includes an inner frame having a lattice shape in which an electrode active material is provided, and an outer frame provided outside the inner frame. A concave portion is formed on the outer surface of the outer frame.

  According to the present invention configured as above, the lead mass can be reduced without impairing the mechanical strength and rigidity of the electrode current collector.

The whole perspective view which shows the structure of the negative electrode collector of this embodiment roughly. The figure which shows the top view and each sectional drawing of the negative electrode electrical power collector of the embodiment. The partial expanded sectional view of the embodiment. The partial expanded sectional view which shows the modification of a negative electrode electrical power collector.

  Hereinafter, an embodiment of a negative electrode current collector used in a lead storage battery according to the present invention will be described with reference to the drawings.

  The negative electrode current collector 1 according to the present embodiment is used for a lead storage battery, and is a standard grid type current collector manufactured by casting such as gravity casting. The lead-acid battery includes a positive electrode plate composed of a positive electrode active material made of lead dioxide and a positive electrode current collector made of lead or lead alloy, and a negative electrode active material made of lead and a negative electrode current collector 1 made of lead or lead alloy. An electrode group constituted by laminating a negative electrode plate constituted by a separator via a separator is immersed in an electrolytic solution. Moreover, as a lead alloy, it is a lead alloy of Pb-0.05 mass% Ca-0.5 mass% Sn, for example.

  Specifically, as shown in FIGS. 1 and 2, the negative electrode current collector 1 has a substantially rectangular shape in plan view, and includes an inner frame 11 having a lattice shape in which an electrode active material is provided, and the inner frame. 11 and an outer frame 12 provided on the outer side.

  The outer frame 12 has a substantially rectangular frame shape provided so as to surround the entire side edge of the inner frame 11. Further, an ear 13 for collecting current connected to the strap is formed on the upper end surface of the outer frame 12 so as to protrude.

  Then, on the outer side surface 12a of the outer frame 12 of the present embodiment, as shown in FIGS. 2 and 3, a recess 121 is formed that is recessed from the side opposite to the inner frame 11 (outer side) toward the inner frame 11 side. ing. As a method of forming the concave portion 121, for example, a method of cutting the outer surface 12a by machining such as milling, or a surface corresponding to the outer surface 12a, not a conventional fixed mold and a movable two-part mold. At least fixed mold, movable mold and side mold divided into three parts, preferably fixed mold, movable mold, left and right side mold, bottom mold with five convex parts on both sides and bottom of conventional mold There is a method of casting using. In addition, an outer surface is a side surface on the opposite side to the inner frame in an outer frame here.

  Specifically, the concave portion 121 is a concave groove that extends along the longitudinal direction of the outer surface 12a in almost all portions of the outer surface 12a except the portion where the ear portion 13 is formed. The cross-sectional shape in the thickness direction of the recess 121 is formed so as to form a substantially U-shape in the present embodiment. Further, the depth dimension and width dimension of the recess 121 are determined by the width dimension and thickness dimension of the outer frame 12, and are set to such an extent that the mechanical strength and rigidity of the negative electrode current collector 1 are not impaired. Note that when the depth of the recess 121 is changed to be a through hole, the mechanical strength of the negative electrode current collector 1 may be weakened.

<Effect of this embodiment>
According to the negative electrode current collector 1 according to the present embodiment configured as described above, since the concave portion 121 is formed on the outer surface 12a of the outer frame 12, without impairing the mechanical strength and rigidity of the outer frame 12, The lead mass of the outer frame 12 can be reduced. Thereby, the lead mass can be reduced without impairing the mechanical strength and rigidity of the entire negative electrode current collector 1 and without reducing the amount of the electrode active material retained. Further, in the negative electrode current collector 1 that hardly deteriorates as compared with the positive electrode current collector, the recess 121 is provided on the outer side surface 12a of the outer frame 12, thereby reducing the life of the lead storage battery. The mass can be reduced.

<Other modified embodiments>
The present invention is not limited to the above embodiment.

  For example, although the negative electrode current collector has been described in the above embodiment, the present invention can also be applied to a positive electrode current collector. In this case, it is necessary to determine the size of the recess in relation to the corrosion of the positive electrode current collector.

  Further, as shown in FIG. 4, in addition to the above-described embodiment, the shape of the recess is a V-shaped cross section (see (a)), a semicircular (semi-elliptical) cross section (see (b)), a parabolic cross section (Refer to (c)), or those having a protrusion (or protrusion) on the bottom of a concave portion having a U-shaped cross section (see (d)).

  Further, in the above-described embodiment, the electrode current collector is described which is a cast-type electrode current collector and the outer frame is provided so as to surround the entire inner frame. However, the outer frame is provided above and below the inner frame. The present invention can also be applied to an electrode current collector (for example, an expanded current collector). In this case, it is conceivable to form a recess on the outer surface of the upper frame portion that is the outer frame provided on the upper portion of the inner frame that is the mesh portion of the expanded current collector or the lower frame portion that is provided on the lower portion of the inner frame. It is done. Moreover, you may form a recessed part in the outer surface of the outer frame of the electrode electrical power collector manufactured by stamping.

  In addition, in the above-described embodiment, the concave portions are formed continuously. However, other concave portions may be formed at regular intervals, for example. Moreover, although the recessed part is not formed in the ear | edge part in the said embodiment, you may form a recessed part also in the outer surface of an ear | edge part.

  In addition, it goes without saying that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

1 ... Negative electrode current collector (electrode current collector)
11 ... Inner frame 12 ... Outer frame 12a ... Outer surface 121 ... Recess

Claims (5)

An electrode current collector made of lead or a lead alloy, comprising an inner frame having a lattice shape in which an electrode active material is provided, and an outer frame provided outside the inner frame,
An electrode current collector, wherein a concave portion is formed on an outer surface of the outer frame.   The electrode current collector according to claim 1, wherein the electrode current collector is a negative electrode current collector.   The electrode current collector according to claim 1, wherein the recess is formed on substantially the entire outer surface of the outer frame.   The electrode for lead acid batteries which has the electrode electrical power collector in any one of Claims 1 thru | or 3, and the electrode active material provided in the inner frame of the said electrode electrical power collector.   The lead acid battery using the electrode for lead acid batteries of Claim 4.