Automobile Enthusiasts

AI recommends 9.6, you mentioned 10.

I've run the car with the 16 year battery installed 3 times today for about 15 minutes each. Interestingly the voltage is going up and now stabilized around 12.2. The CCA reading was 8.6 this morning, 8.8 at 2 pm and now 9.0 after dinner. I will leave it until tomorrow am.

I'm really not trying to avoid buying a new battery, I have one all priced up, my concern being this is apparently a quality unit, and I'm very curious to see where the CCA levels out.

The other battery, the 4 year one, simply would not hold a charge. It would no longer charge above 12.1, and most alarmingly when it was on the lawn mower charger the charging voltage wouldn't go above 12.4 and then it would drop back immediately. Tiime was it could charge at 13.4. Something really bad about that battery.

Here's what GOOGLE AI had to say about CCA recovery:

CCA (Cold Cranking Amps) represents a battery's ability to deliver a burst of energy to start an engine, particularly in cold temperatures
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Here's how CCA can be affected by a discharged battery and the potential for recovery:

CCA decline with discharge and age: As a battery ages and undergoes charge/discharge cycles, its CCA rating naturally diminishes. Deep discharges can accelerate this process and negatively impact overall battery performance, including CCA.
Stratification and Low Charge: A common cause of low CCA readings is stratification, which can result from a low charge or infrequent use. Stratification is a condition where the electrolyte separates into layers of varying density, leading to an artificially low CCA reading.
Reversibility of Stratification: In many cases, stratification is reversible. Fully charging a battery after resting it can help restore the electrolyte to a more uniform density and improve CCA performance.
Impact of Deep Discharges: While some deeply discharged batteries can be recovered, they rarely return to their full capacity or performance. Repeated deep discharges can lead to sulfation, where lead sulfate crystals harden on the battery plates, reducing the battery's ability to hold a charge and deliver power. If the sulfation becomes permanent, the battery may not be recoverable.
Importance of Proper Charging: Using a charger designed for lead-acid batteries and ensuring a full recharge after discharge is crucial for maintaining optimal CCA and battery life. Avoid prolonged deep discharges and ensure regular battery maintenance, including keeping terminals clean and free from corrosion, to help preserve CCA performance.

In essence, recharging a discharged battery can help recover its CCA, especially if the discharge wasn't excessively deep and the primary issue is stratification. However, if deep discharges have occurred, the recovery may be limited, and the battery's overall capacity and lifespan may be reduced.

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So maybe I did the battery some good by shaking it vigorously left and right, tilted too. I think I'm going to get one of these $20 everything battery and charge units ... maintainer, charger, diagnoses, desulfate and more.