I have quite a few "Power Sonic" lead-acid batteries with varied life histories. I'd like to be able to test them to see if they still can hold a charge nearly as well as they originally did. I think some discharge quicker than others, but because they are used sporadically in test instruments that I turn on and off during jobs, I really have no reliable way of knowing whether they supported the instrument for ten minutes or two hours before needing recharging.
Last night, I drained and charged a couple of these batteries. I drained them by leaving the instrument they are powering on until the battery failed, and then left it on for some time after that, reducing their no-load outputs to 9-10 volts. Then I charged them for about four to five hours using the instrument's internal charger (a "dumb" charger), then I powered up the instrument again, recording the voltage level every maybe 15 minutes or so until it failed again.
I did that with two batteries. One supported the instrument for about two hours, which I think is normal. The other for about half an hour, which I think is unacceptably out-of-spec. I could continue with this test with other batteries and other loads, but the fact is, I can replace these batteries for about fifteen dollars each, so even if I ever develop an effective and reliable regimen for evaluating the health of these batteries, implementing it will cost me more than these batteries are worth.
What is available for testing the health of lead-acid batteries? I would think that, in addition to the battery's nominal output voltage level, there would have to be some provision for informing the test device of what the rated amp/hour capacity of the battery was.
Last night, I drained and charged a couple of these batteries. I drained them by leaving the instrument they are powering on until the battery failed, and then left it on for some time after that, reducing their no-load outputs to 9-10 volts. Then I charged them for about four to five hours using the instrument's internal charger (a "dumb" charger), then I powered up the instrument again, recording the voltage level every maybe 15 minutes or so until it failed again.
I did that with two batteries. One supported the instrument for about two hours, which I think is normal. The other for about half an hour, which I think is unacceptably out-of-spec. I could continue with this test with other batteries and other loads, but the fact is, I can replace these batteries for about fifteen dollars each, so even if I ever develop an effective and reliable regimen for evaluating the health of these batteries, implementing it will cost me more than these batteries are worth.
What is available for testing the health of lead-acid batteries? I would think that, in addition to the battery's nominal output voltage level, there would have to be some provision for informing the test device of what the rated amp/hour capacity of the battery was.