There is so much terminology related to stationary batteries that it is hard to know what everything means. We recently received a question through our FAQ section asking what the difference is between jars and straps, so we thought it would be a good time to discuss this with our blog readers.

What is a jar?
A stationary battery jar is the container that holds the cell or group of cells and electrolyte. It is also commonly referred to as a battery case or cell case.

Jars are typically made out of some kind of thermoplastic substance. However, hard rubber is sometimes used as well. If the battery contains nickel-cadmium cells, the jar may even be made out of steel. Vented lead-acid batteries in North America normally have transparent jars to allow for plate and sediment inspection.

What is a strap?
A stationary battery strap is the component in a cell that joins plates of like polarity in parallel.

It is an electrical conductor that is made of copper. It typically has a lead or tin plating for lead-acid cells. Nickel-cadmium cells require a different connector. They are typically made with nickel-, cadmium-, or tin-plated copper. They may even use a steel bar.

Sometimes the strap may be insulated copper wire or lead (with or without a copper insert) for lead-acid batteries. It depends on the manufacturer’s specifications.

For more stationary battery terminology, check out our blog post 17 Stationary Battery Terms to Know.