Cycle life testing of a battery is a long, expensive, and b-o-r-i-n-g exercise. At least ten specimens have to be chosen at random, not of the same production batch.
I had to manufacture my own equipment from scratch. Nichrome resistance wiring with the durability overkill percentile that would make a book keeper scream in agony. Resistance comparability of ten circuits measured with a four wire milli-ohm meter then verified with a precision power supply and Manganin shunt to be positively assured all ten circuits were ABSOLUTELY identical. Amperage draws were within a HUNDREDTH of an ampere equal all 10 circuits.
OMRON precision interval timers with an accuracy of .001 second. A master power supply 200 amperes for group 24 RV batteries. Silver soldered connections, silver cadmium interface compound to join to battery posts.
10 Precision kWh meters in series with the negative leads. The meters had to be qualified before and after the tests.
42.5 ampere hour discharges at 05 amperes discharge rate. More than 8 hours discharge and 6 hours to recharge. Fourteen hours per cycle. Three hundred cycles.
1. Full conditioning (top charge)
2. kWh discharge to 12.00 volts, establishes available kWh available energy.
3. Hydrometer sampling
4. Drain and extract plates and lid
5. Autopsy positive and negative plates
6. Issue report of findings.
Now someone is going to tell me that some Gyro Gearloose peddling a pulse modulated power supply went through a similar protocol to verify whether or not their gizmo had any effect at all on points (1) through (5) as compared to normal charging and discharging cycling?
I tested batteries for N.A.S.A. and DOD because many fellow engineers understood my protocol and discipline. When I see the free-for-all atmosphere that exists in battery marketing today I cringe and get moody. It just isn't with batteries, we have RV tires that explode, a government of do-nothing drones that cannot put together a testing regimen requirement for manufacturers to meet and prove standards. Man what a mess we have. OK I'll get off the soap box now...
