Gary Rinsem

Battery Analyzer
by Gary Rinsem

Why analyze a battery? Because they're very expensive and sometimes need repair. The largest of electric forklift batteries weigh as much as two small cars and cost a fortune to replace. Repairs are usually a couple thousand dollars. Tests are performed to determine if it's worth repairing and how to repair them. My battery analyzer was a combination of hardware and software which I developed. Batteries are connected to a PC through electronic hardware, allowing the software to monitor and log the voltage of each cell as the battery is either rapidly charged or discharged. The alternative is for a technician to constantly write the voltages of 24 cells, using a voltmeter. Tests can take many hours and no person can accurately record the voltages more than every five minutes. Nobody can maintain that pace for hours. GR Battery Analyzer accurately read every cell voltage ten times a second, for weeks if needed. The program was sitting around bored most of that time. So what does it do? Most obvious is the graph of the data it collected. It also analyzes that data and tries to make recommendations about repairs. During the testing process, the software is looking for problems which could cause further damage if the test continues. It sounds an alarm in that situation to tell the technician to stop the test. Does it do anything else? Hell yes... It will create a web page for the customer telling all about the battery. Technicians can include their analysis of the battery and sales people can include their message to the customer, ideally a repair quote. There's more, but I'm sure anyone who reads this far, will be bored to tears by now.

Test during charging of a battery with a bunch of bad cells. It looks like the test was cut short, long before the battery was charged. It was dangerous to let the test go on as long as it did. Individual cells in this condition can explode violently when charging.

This is a battery after it was repaired. Notice the first half of the test when it was charging. It looks like a new battery. The second half during a load test also looks like a new battery.

I still have the schematic so here it is. I chopped the size way down from the original, but it should be legible if opened in a new tab.