Acid Resistant Clear Temporary Protective Coating

No REZ® 2-COS :Battery Fabrication Flux- Halide Free COS Soldering Flux

  • Specially developed to enhance the quality of Battery Fusion
  • Formulated to perform cleaning & joining of lugs & straps in most cast-on strap operations
  • Solvent based flux contains no halides such as chlorides  or heavy  metals (Work environment safe) which does not harshly coorde assembly equipment.
  • General Chemical’s soldering fluxes are in use throughout the world for more than 25 years
  • Wide window of operation
  • low fuming
  • Non Flammable


solvent -based flux Super concentrate, the No Rez soldering compound-No Rez ® 2-cos is used for joining lead alloys together or for fusing vdarious metals with tin/lead solder. It has found excellent acceptance in the battery assembly field because of its non-corrosive tendencies once the fusion operation is complete.

No REZ® 2-COS battery fabrication flux is designed to work for high volume cast-on strap manufacturing. No REZ® 2-COS solvent-based flux contains no chlorides or heavy metals to effect long-term performance, and is environmentally safe. It offers wide window of operation. Whether running at low temperatures due to straps cracking or high temperatures to accommodate large mass plates, 2-cos provides consistently strong bonds.

No REZ® 2-COS provides consistent metal Joining for all lead battery alloys and is especially effective in joining dissimilar alloys as in cast-on-strap manufacturing. No REZ® 2-COS low fuming or smoking, leaves minimal residues after fusing, and is not highly corrosive. It solder bond is porosity-free enhancing soldered quality.
I receive the results from the cross-sectioned straps today, the results confirm that the flux produces straps with minimum gas voids & in fact it has produced the best straps of any of the fluxes I have tried to date. The lug to strap fusion is poor compared existing flux production, this is more to do with lug preparation than your flux. Bottom line (one of the world’s largest battery manufacturer) needs to do further work on the COS operation & pre-conditioning of the lug surface & once this work has been completed I would be interested in pursuing your flux further.


General Chemical’s fluxes are being used at world’s largest to any size battery plants for over two decades. It is being shipped to Jordan, Austria. Brazil, Bulgaria ,China, Chile, United Kingdom, Korea, Mexico, Taiwan, USA and other countries.


Use as supplied No Rez Ò 2-COS flux functions in the following manner:

1. The flux wets the lead alloy of the plate lugs and does the final cleaning of the metal surface.
2. 2-COS acid complex chemically reduces the surface oxides.
3. When heat is applied to the lugs, the water and solvents are driven off in a gaseous state.
4. The residual liquid-crystal formation remains stable until the lead alloys join via the capillary action of the flux.
5. When the fusion between the lugs and the strap is complete, the flux residue is virtually non-hygroscopic and non-corrosive.

This, in essence, makes No Rez Ò 2-cos solvent base flux superior to all Other fluxing compounds including rosin fluxes applied in the battery construction process.

Specific Gravity 1.12Clean equipment with Water
Flash Point>200F/93C(CC)Boiling Point220F/104C
ColorRedpH of concentrate3 to 4



can be applied by dipping, spraying, or brushing and will function in closed or open systems. It has long working life in the flux pot and if necessary may be thinned with water.

Rubber gloves (impervious to acid) and safety glasses are required when
handling or mixing flux solution.

Keep skin contact to a minimum. Wash exposed skin area with water.

Wash any clothes that have been splashed with flux.

A protective hand cream is recommended when handling flux.


Use plastic (or impervious to acid) equipment when handling flux. Use a 5-gallon container to prepare a solution of flux for use.

Precipitation( crystal formation) when flux 2-cos is exposed to cold temperatures for an extended period. 2-cos can be redissolved by following procedure:

  1. To dissolve the crystals in the flux, the container can be heated to 125f/52c for 2 to 3 days.
  2. The flux should be heated to evenly heat the container and avoid localized heating.
  3. Heating can be done by placing container in a room or other heated area to the constantly monitored temperature.
  4. Whenever suitable container is not available , use stainless steel container for heating the flux to redissolve the crystals.
  5. In all cases frequently stir during the process until all crystals have dissolved.
  6. Once all crystals have dissolved , let the 2-cos be cooled to ambient temperature.
  7. Stir the solution after adjustment and take another meter reading to Verify


Note: The information presented herein is our interpretation of certain test results and field experience to date. The information is not to be taken as warranty or representation for which we assume legal responsibility, nor as permission or recommendation to practice any patented invention without a license. It is offered solely for your consideration, investigation and verification