A battery management system can help users avoid premature battery failure, underperformance, or both. But there are bigger picture implications, too. It can reduce the required number of lift truck, pallet truck, or AGV batteries by up to 50%. This decrease in the number of batteries can minimize the overall cost of charging and maintaining batteries by 25% or more.
A system can also boost staff productivity. Changing batteries at the proper time rather than during peak periods, like shift changes, can add 30 minutes or more of productive work per lift truck each day. The money saved by increasing the efficiency of the floor operations and the reduction in maintenance and charging costs can result in an ROI (on the purchase of the management system) in as little as nine months.
While battery rotation, washing, watering and equalizing are important, tactical concerns are not the whole story. It pays to think strategically.
Just as the bulk of an iceberg goes unseen beneath the surface of an ocean, a mass of battery information is available but goes unused. Here are some tips to help everyone — from operators in the battery room to logistics managers in corporate offices — get the most out of a warehouse battery management system.
Battery Management's Stakeholders
Operators and maintenance supervisors need only tactical information such as:
When does a battery need to be watered, washed, or equalized?
Which battery is next in rotation to be placed in a lift truck?
Which batteries, chargers, or forklifts are underperforming and need further evaluation?
Facilities managers will ask more strategic questions:
Does my battery inventory meet my forklift energy needs?
Do I have excess battery inventory?
Are my batteries lasting as long as they should?
How do I document battery warranty claims?
Are my batteries maintained properly?
Corporate executives will need even more information to fully analyze their assets at various levels, in multiple facilities:
How is one facility performing compared to another?
Do I have adequate or excess assets (at one facility vs. another)?
How can I best allocate my assets?
If one facility performs better, why?
Can we employ best practices to all facilities?
To adequately answer the questions for each of these various managers, it's essential to choose a battery management system that tracks at least seven basic data points:
An asset ID for the lift vehicle
An asset ID for each incoming battery
An asset ID for each outgoing battery
An ID for each individual operator
A time stamp for the moment that each battery transaction begins and ends
How long each truck ran on each battery, obtained from the hour meter (run-time)
The charging location for the outgoing battery
Each of those seven points of data is equally important to thoroughly evaluate battery-powered operations. Because a system time-stamps virtually every change of state as a battery is charged, cooled, installed and used, it provides the key metric of run-time.
“Knowing run-time, or how long a forklift actually moves or lifts product, is critical since it tells you how much actual work you got out of your battery,” says Terry Orf, administrative vice president at Materials Transportation Company (MTC), battery management system providers. “Clock-time, or how long a battery has been sitting in a forklift, is relatively meaningless unless you have run-time as well.”
Turning Data into Information
What's needed is to turn data into useful information. The ability to slice, dice and interpret data gives managers the visibility into the operations they need to create savings and encourage higher productivity.
Evaluating battery performance on run-time, for instance, does more than allow organizations to quickly zero in on which batteries may be worn out or simply need to be watered. It's a great overall indicator of how an entire operation is running, especially when coupled with metrics like operator performance.
“Because we collect the timestamp when forklift operators come in for a battery change, we can see if everybody comes in at shift change or throughout the day,” says Orf. “We can see if they're using the battery change as a break, which can happen if several people line up.”
The solution: “Spread battery changes throughout the day, which minimizes wait time and the number of batteries you need to buy, inventory, charge and maintain,” says Orf. “Industrial engineers or facilities managers can help achieve this by reviewing a transaction report and specifying that operators only come in for a battery change when the battery is 80% discharged.”
Battery management systems can help managers see the “big picture,” like when, why and how often forklift operators are choosing or re-choosing the wrong battery. By running an operator re-choose report, managers can quickly figure out and correct poor operator decisions.
“If nearly everyone is choosing the wrong battery, it's clear that they need additional training,” says Orf. “If a single person is repeatedly choosing the wrong battery, they too may need additional training. Or they may simply need to be reminded to take the right one, as opposed to the closest one.”
User-defined reports can be exported to spreadsheets and other programs. Also necessary is the ability to sort data within reports without having to export it. This flexibility is required to manipulate the data as needed and provide a manager with information that is unique to their particular operation.
From a corporate-wide perspective, broad scalability is required to allow one battery management system to work with the entire scope of assets and facilities within that organization. Having enough user-defined vehicles, chargers, batteries and battery types available can allow for comparison and benchmarking of battery performance between facilities.
Ideally, data should reside on a company's own PCs as opposed to offsite data locations. This allows easy month-to-month or year-to-year comparisons without subscriptions and storage or downloading limitations that may make accessing historic information difficult.
One Fortune 500 distribution warehouse that ran three batteries per lift truck cut their battery use in half based on analysis of their operations, runtimes and other factors. They were able to reduce their inventory by 60 batteries for $250,000 in savings.
The immediate and ongoing payoff of using a battery management system is spurring more company managers to optimize their motive equipment operations with the improved tactical and strategic capabilities that such systems provide.
Del Williams is a technical writer based in Torrance, Calif.
For more information about battery management systems, visit www.ebattsystems.com .