Chemistry: electrical current producing apparatus – product – and – Current producing cell – elements – subcombinations and... – Separator – retainer or spacer insulating structure
Patent
1996-10-03
1998-07-07
Willis, Jr., Prince
Chemistry: electrical current producing apparatus, product, and
Current producing cell, elements, subcombinations and...
Separator, retainer or spacer insulating structure
429146, 429147, H01M 218, H01M 216
Patent
active
057766304
DESCRIPTION:
BRIEF SUMMARY
The invention relates to separators for accumulators preferably in the form of material taken from the roll not cut to size. The separators are provided at least on one side with a pattern of longitudinal and transverse ribs which increases the rigidity of the separators both in the longitudinal and transverse directions and prevents a distortion of the separator sheet by coiling operations.
The separators which are used today in accumulators are formed from microporous sheets, which prevent short circuits between the plates and the falling out of plate material. However, by reason of their pore structure they permit an ionic flow of current in the electrolyte. Separators of this type are normally provided at least on one side with longitudinal ribs which should prevent the direct contact of the separator sheet with the positive electrode plate. At the same time these ribs give the separator a certain rigidity in the longitudinal direction. The separators consist generally of a thermoplastic material and are formed into pockets, into which the positive or negative electrode plate is inserted. The height of the ribs is usually greater than the thickness of the separator sheet which results in a relatively unfavourable torque for forces acting at the ribs which in conjunction with the plasticity of the plastics used frequently results in distortions of the separator. Distortions of this type occur particularly when the finished separator tracks are rolled up. As a result of this the separators are no longer even which causes serious problems during subsequent cutting to size and further processing into pockets. Their low rigidity in the transverse direction is also a disadvantage on the known separators.
Rigid separators for electrical accumulators are described in German patent specification DE-PS 28 47 453, for which a microporous base material is thermally bound to a network structure made of stretch plastic. The webs of the stretch plastic have different thicknesses and thus facilitate the escape of electrolytic gases. These separators have an increased bending strength in all surface directions. A disadvantage of these separators is that the network structure and the base material are manufactured independently of each other and then have to be joined together in an additional process step. In addition the network structure of the stretch plastic layer does not allow the electrolytic gases to rise in a straight line but forces the gas bubbles into a zig-zag shaped pattern. The battery separators disclosed in the German patent specification DE-PS 28 47 463 are rigid separators which are inserted in sheet form into the accumulator housing. The handling of rigid separators of this type is relatively difficult so that interest in them is decreasing. Furthermore the structure of the separators disclosed in DE-PS 28 47 463 does not allow them to be further processed to form pockets as is usual currently.
The object of the present invention is to provide separators for accumulators which have an increased rigidity both in the longitudinal and transverse directions and which are provided with ribs which can be manufactured integrally, i.e. at the same time as the porous separator sheet and which enable the charging gases to escape rapidly and in a straight line. The separators should preferably be provided in the form of rolls which are simple to handle and which can easily be further processed to form pockets.
The subject matter of the invention is a separator for accumulators which in addition to the longitudinal ribs which run in the direction of manufacture is provided with ribs which run transversally to it. The transverse ribs have a smaller height by comparison with the longitudinal ribs. The separators are disposed in the accumulator in such a way that the longitudinal ribs run vertically and the transverse ribs horizontally so that a channel is created by the reduced height of the transverse ribs which enables the charging gases to escape easily and in a straight line. The transverse ribs can be produc
REFERENCES:
patent: 662277 (1900-11-01), Leitner
patent: 1331018 (1920-02-01), Luthy
patent: 4618545 (1986-10-01), Clegg et al.
patent: 4927722 (1990-05-01), Bohnstedt et al.
Copy of the International Search Report dated Sep. 3, 1995.
Chaney Carol
Daramic, Inc.
Willis Jr. Prince
LandOfFree
Separator with longitudinal and transverse ribs for use in accum does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Separator with longitudinal and transverse ribs for use in accum, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Separator with longitudinal and transverse ribs for use in accum will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1203685