Other Voices: Lean thinking in the industrial battery room

Editor’s Note: The following column by Harold Vanasse, vice president of sales and marketing for Philadelphia Scientific, is part of Modern’s Other Voices column. The series features ideas, opinions and insights from end-users, analysts, systems integrators and OEMs. Click here to learn about submitting a column for consideration.

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Over the past 100 years, Lean principles have gradually made their way from the manufacturing environment to the warehouse – and finally to the battery room.

But is Lean thinking really needed in the battery room? Battery room activities are typically seen as ancillary to the warehouse’s main business of storing and distributing. The problems that can be found in the battery room are generally considered to be relatively insignificant.

But these beliefs are based upon a lack of clear understanding about the magnitude of waste in the typical battery room. In fact, a poorly run battery room actually creates additional waste throughout the entire warehouse.

Where waste can be found in the battery room
A key tenet of Lean thinking is that you cannot change or improve what you have not measured. Feedback is required for continuous improvement, and the four basic steps of the Lean process are geared to achieving that improvement:

1. Identify waste and make a plan to reduce it
2. Implement plan
3. Measure actual performance
4. Evaluate actual performance compared to plan; make adjustments

When battery room activities are carefully studied, it becomes apparent that six of the eight types of waste can be found there. (Only two Lean wastes – over-producing and over-processing – are missing.)

1. Transportation: Unnecessary trips to the battery room to change batteries due to inadequate information on the charge state of the battery being used.
2. Inventory: More batteries and chargers in the fleet than are needed for the required work.
3. Motion: Battery changing and battery watering processes that require more movement than is necessary.
4. People: Too many people watering and charging batteries, some with skills that could be best put to use elsewhere in the warehouse.
5. Waiting: Operators queuing for battery changes due to poor charging practices; operators waiting during slow battery watering practices.
6. Defects: Operator selection of the wrong battery, which can shorten battery life, costing money; too much or too little water added during battery watering, which shortens battery life and may cause a hazardous condition due to electrolyte boil overs.

Studies and anecdotal evidence show that waste in the battery room can cost large warehouses and DCs hundreds of thousands of dollars per year – and smaller operations with as few as 10 to 20 forklift trucks as much as tens of thousands of dollars due to these wastes.

Understanding six key aspects of battery maintenance and use
So, how does one tackle the task of eliminating waste in the battery room? In order to maximize a battery’s useful life, managers should understand six basic aspects of battery maintenance and use:

1. Charging: Batteries should be fully charged to ensure the electrolyte is properly mixed. Never disconnect charger cables from the battery during the charge, as this may damage the connectors and create a possible explosion hazard. Allow batteries to cool down before using, as excessive heat shortens battery life. A common industry recommendation is a minimum of eight hours of cool down time.
2. Discharging: Batteries should be fully discharged. Partial discharges increase the number of cycles, decreasing operator productivity. Over-discharging can result in permanent battery damage.
3. Cycling: Under-cycling batteries creates corrosion even when batteries are not being used, wasting cycles. Over-cycling, which gives batteries inadequate time to cool down, causes corrosion due to increased heat, shortening battery life and reducing the number of cycles.
4. Watering: Under-watering a battery exposes the lead plates to air, which causes the plates to sulfate and lose capacity. Over-watering batteries reduces their capacity – a three percent capacity loss with each electrolyte boil over. Watering with deionized or distilled water is important, too, as dissolved minerals found in most tap water can cause battery damage, reducing battery life.
5. Cables and Connectors: Repair broken cables. Short circuits are a fire and safety hazard. And repair broken connectors. Intermittent contact can damage chargers and create dangerous arcing.
6. Washing: Regular washing of batteries minimizes short circuits across the surface of the battery, reduces energy loss and minimizes tray corrosion.

Eliminating waste in the battery room
This background on battery operation and maintenance will help managers begin the process of attacking waste in the battery room. To achieve measurable and sustainable elimination of waste, managers need to focus on the three major impacts on battery room operation and maintenance: Rotation, Rightsizing and Watering – the subjects of the next three articles in this series.

Harold Vanasse is vice president of sales and marketing for Philadelphia Scientific. He can be reached at 215-616-0390 or [email protected].