GB1575280A - Battery terminal connector - Google Patents

Description

(54) BATTERY TERMINAL CONNECTOR (71) We, CHLORIDE GROUP LI MITED, a Company registered under the laws of England, of 52, Grosvenor Gardens, London SW1W OAU, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed to be particularly described in and by the following statement.

This invention relates to the sealing of a terminal connector from a battery cell in a hole in the battery case.

For example in an electric storage battery having a lead acid electrolyte with an external connector sealed in the battery cover, difficulty is experienced in preventing acid from attacking any seal around the terminal connector or post, and eventually leaking. Frequently such terminal connectors are of lead, or are coated with lead, and it has been found difficult to establish an effective seal around a lead surface.

According to the present invention, in a method of sealing a terminal connector from a battery cell, in a hole in the battery case, a terminal connector extends through a hole in the case with a layer of hot melt adhesive around the connector and a sleeve of heat shrink material around the layer, and a hot sealing compound is applied between the hole and the sleeve to shrink the sleeve on the layer and to seal the sleeve in the hole.

It has been discovered that although it is difficult to get a hot melt adhesive to seal effectively with a lead surface under normal conditions, provided the hot melt adhesive can be put under compression, it can seal effectively with the lead surface and prevent the seal being destroyed by the action of lead acid. Thus when the heat sealing compound is applied to fill and seal the space between the outside of the sleeve. and the hole. the heat of the compound shrinks the heat shrink material at the same time to put the hot melt adhesive under compression, and effect a good seal in quite a simple way.

The heat shrink material is conveniently polyethylene and that might be in the form of a tube, or it might be in the form of a wound-on tape. In either case it is possible to line the heat shrink material with the hot melt adhesive so that both layers are provided in the same operation.

A temperature of say 1200 - 130"C may be quite suitable for shrinking the polyethylene to put the hot melt adhesive under sufficient compression to establish the seal.

The hot sealing compound could conveniently be the same material as is used for the hot melt adhesive between the connector surface and the heat shrink material.

The invention includes a storage battery having a terminal connector sealed in a hole in the battery case by a method as defined above.

The invention may be carried into practice in various ways, and one embodiment will now be described by way of example with reference to the accompanying drawing, of which the single figure is a sectional elevation through a part of a lid of a battery case through which a terminal post leads.

The terminal post 11 is of lead and extends upwards from a plate strap 12 through a hole 13 in the end wall of a well 14 defined in the lid 15.

The part of the post extending through the hole is coated with a hot melt adhesive 16, and that is in turn surrounded by a polyethylene sleeve 17.

After the lid 15 is positioned in relation to the post 11 as described, a hot melt sealing compound 18 is introduced into the well 14 and extends down into the hole 13 to provide an effective seal between the lid 15 and the polyethylene sleeve 17. The heat of the compound 18 causes the sleeve 17 to shrink and that puts the hot melt adhesive 16 under compression where it is surrounded by the sleeve and when the adhe sive is under compression, it seals effectively with the external lead surface of the post 11.

There is thus effected a complete seal between the terminal post and the lid against the intrusion of acid from the cell between any pair of sealed surfaces.

An effective seal is made quite simply because the compound 18 is used not only to seal the external surface of the sleeve 17 to the lid 15, but its heat is used to shrink the sleeve 17 and of course the compound fills the gap around the srunk sleeve.

WHAT WE CLAIM IS: 1. A method of sealing a terminal connector from a battery cell in a hole in the battery case, in which a terminal connector extends through a hole in the case, a layer of hot melt adhesive is around the connector and a sleeve of heat shrink material is around the layer, and a hot sealing compound is applied between the hole and the sleeve to shrink the sleeve on the layer, and to seal the sleeve in the hole.

2. A method as claimed in Claim 1 in which the heat shrink material is polyethylene.

3. A method as claimed in either of the preceding claims in which the heat shrink material is in the form of a tube.

4. A method as claimed in Claim 1 or Claim 2 in which the heat shrink material is wound on as a tape.

5. A method as claimed in any of the preceding claims in which the heat shrink material is lined with a hot melt adhesive.

6. A method as claimed in any of the preceding claims in which the hot sealing compound is the same material as the hot melt adhesive.

7. A method of sealing a terminal connector from a battery cell in a hole in the battery case, performed substantially as herein specifically described with reference to the accompanying drawing.

8. A storage battery having a terminal connector sealed in a hole in the battery case by a method as claimed in any of the preceding claims.

9. A storage battery having a terminal connector sealed in a hole in the battery case, substantially as herein specifically described with reference to the accompanying drawing.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (9)

**WARNING** start of CLMS field may overlap end of DESC **. sive is under compression, it seals effectively with the external lead surface of the post 11. There is thus effected a complete seal between the terminal post and the lid against the intrusion of acid from the cell between any pair of sealed surfaces. An effective seal is made quite simply because the compound 18 is used not only to seal the external surface of the sleeve 17 to the lid 15, but its heat is used to shrink the sleeve 17 and of course the compound fills the gap around the srunk sleeve. WHAT WE CLAIM IS:

1. A method of sealing a terminal connector from a battery cell in a hole in the battery case, in which a terminal connector extends through a hole in the case, a layer of hot melt adhesive is around the connector and a sleeve of heat shrink material is around the layer, and a hot sealing compound is applied between the hole and the sleeve to shrink the sleeve on the layer, and to seal the sleeve in the hole.

2. A method as claimed in Claim 1 in which the heat shrink material is polyethylene.

3. A method as claimed in either of the preceding claims in which the heat shrink material is in the form of a tube.

4. A method as claimed in Claim 1 or Claim 2 in which the heat shrink material is wound on as a tape.

5. A method as claimed in any of the preceding claims in which the heat shrink material is lined with a hot melt adhesive.

6. A method as claimed in any of the preceding claims in which the hot sealing compound is the same material as the hot melt adhesive.

7. A method of sealing a terminal connector from a battery cell in a hole in the battery case, performed substantially as herein specifically described with reference to the accompanying drawing.

8. A storage battery having a terminal connector sealed in a hole in the battery case by a method as claimed in any of the preceding claims.

9. A storage battery having a terminal connector sealed in a hole in the battery case, substantially as herein specifically described with reference to the accompanying drawing.