How to Convert Cold Cranking Amps (CCA) to Amp Hours (Ah)

Cold Cranking Amps (CCA) to Amp Hours (Ah)

The conversion of cold start amps (CCA) to ampere-hours (Ah) is not a direct conversion because CCA and Ah are different units used to measure different aspects of battery performance.

Cold start ampere (CCA) is a measurement used to determine the ability of a battery to start an engine at low temperatures. It represents the amount of current a battery can deliver at 0 degrees Fahrenheit (-17.8 degrees Celsius) for 30 seconds while maintaining voltage above a specified level (usually about 7.2 volts for automotive batteries).

The ampere-hour (Ah), on the other hand, is a measure of a battery’s ability to deliver a certain amount of current over a certain period of time. It represents the total amount of charge a battery can deliver in one hour.

CCA to Ah

To convert CCA to Ah, you need additional information about a battery’s rate of discharge or capacity in Ah.

If you have data on a battery’s capacity in Ah, you can estimate its CCA by considering the value of the Pevkert exponent. The Pevkert exponent is a measure of how well a battery can deliver current at different discharge rates. Using Pevekert’s Law, you can estimate the CCA rating from the capacity in Ah.

In this article, I will explain how to convert CCA to Ah in practice.

Cranking Amps to Amp-hours

Cranking Amps (CA) is a measurement used to determine the ability of a battery to start an engine at a certain temperature. It represents the amperage that a battery can deliver at a certain temperature for 30 seconds while keeping the voltage above a specified level.

Ampere hours (Ah), on the other hand, is a measure of a battery’s ability to deliver a certain amount of current over a certain period of time. It represents the total amount of charge a battery can deliver in one hour.

To convert amperes (CA) to ampere-hours (Ah), you will need additional information about the battery’s rate of discharge or its capacity in Ah.

To estimate the amp-hour capacity from cranking amps, you can use Peukert’s Law formula, which takes into account the battery’s discharge rate:

Ah = CA / (k * (CA / 10)^m)

In this formula:

• Ah = Amp-hours
• CA = Cranking Amps
• k = Peukert’s constant (typically ranging between 1.1 and 1.4 for lead-acid batteries)
• m = Peukert’s exponent (a value that depends on the battery’s characteristics)

Ah to CCA

To determine cold run amperes (CCA) from ampere hours (Ah), you can use the following formula:

CCA = (Ah * 1000) / (Discharge time in seconds * Puckert exponent).

In this formula:

• Ah represents the capacity of the battery in ampere-hours.
• Discharge time represents the length of time a battery takes to discharge, usually in seconds.
• Pevkert’s exponent is a measure of the rate of discharge of a battery.

Conversion table between cold amps (CCA) and ampere-hours (Ah)

This is a table that gives a general estimate of the conversion between cold run amps (CCA) and ampere-hours (Ah) for automotive batteries:

Why do I need to convert cold start amps to ampere-hours?

Car batteries have many characteristics that you should know about if you are going to buy a new battery for your car.

Today’s cars use many electronic components, and you should choose the right battery for your car. Converting CCA to Ah is handy to determine if the battery is right for your particular car.

The conversion between cold start amps (CCA) and ampere-hours (Ah) is not straightforward. Cold start current (CCA) and ampere-hours (Ah) describe the capacity of a battery and its ability to provide current for some time – these are just two extremes of battery use.

You cannot directly convert CCA to AH because there is no correlation between the two. But for practical purposes, you can divide the CCA by 7.25 to get an estimated Ah value. For example, if your battery is labeled 1450 CCA, this corresponds to 200 Ah.

Cold Cranking Amps (CCA) and Ampere Hours (Ah)

CCA (Cold Cranking Amps) is the value of the maximum current specified in amperes that a new, fully charged 12 V battery can deliver for 30 seconds, with the voltage NOT dropping below 7.2 V at 0°F (-18°F). С).

Of course, there are several definitions of the CCA value, depending on the standard, but this is the most common.

Capacity is a value that directly describes the capacity of a battery and is expressed in ampere-hours (Ah).

The capacity of a new, fully charged 12 V lead-acid battery is the DC discharge current applied for 20 hours without the battery voltage dropping below 10.5 V, at 80°F (~27°C), multiplied by 20 hours.

Battery capacity is the amount of electrical energy a fully charged battery can deliver at a specific discharge mode and temperature from initial to final voltage. The SI unit for electrical charge is the Coulomb (1Cl), but in practice, capacity is usually expressed in ampere hours (Ah).

Capacitance is measured in ampere-hours and is determined by the formula:

C=Ip * tp

• where C is capacity, Ah;
• Ip – discharge current strength, А;
• Tp – discharge time, h.

The nominal capacity is the capacity that a new fully charged battery should give under normal discharge conditions specified in the standard for that battery. The voltage must not drop below a certain value.

Because capacity is a function of discharge current and final discharge voltage, the battery designation indicates the capacity corresponding to a specific discharge mode. For starter batteries, the nominal capacity is taken as the capacity at 20 hours, stationary batteries at 10 hours, traction batteries at 5 hours of discharge.

An example of the assessment of a battery capacity under the 20-hourly discharge regime with a current of 0.05 C20 (5% of the nominal capacity).
If a battery is 55Ah, then a 2.75A current will fully discharge it in 20 hours. Similarly, for batteries with a capacity of 60Ah, a full 20-hour discharge will occur at a slightly higher discharge current of 3A.

Capacity output is the ratio of the amount of electricity received from the battery on discharge to the amount of electricity needed to charge the battery to its original state under certain conditions.

It depends on the completeness of the charge. Part of the charge is lost to gassing, which reduces the capacity factor.

Residual capacity is the amount of electricity that a partially discharged battery can give off in the specified mode of discharge to its final voltage.

Reserve capacity of the battery – the time during which the battery will be able to ensure the operation of consumers in the emergency mode. The value of the reserve capacity, expressed in minutes, is lately more often put by the manufacturers of starter batteries after the value of the cold start current.

Charging capacity is the amount of electricity delivered to the battery during charging. The charging capacity of the battery is always greater than the discharging capacity due to the loss of energy for side reactions and processes.
When the charging current l is constant, the charging capacity is C= I * t, where t is the charging time.

Capacity measurement is carried out until the voltage drop of at least one battery cell to the value regulated for a particular discharge mode.

During the service life the capacity of the battery varies. At the beginning of life, it increases as the active mass of the plates develops. During the service life the capacity remains stable for some time, and then starts gradually decreasing due to the obsolescence of the active mass of the plates.

The capacity of the battery depends on the amount of active material and electrode design, the amount and concentration of the electrolyte, the magnitude of the discharge current, electrolyte temperature, the degree of battery wear, the presence of foreign impurities in the electrolyte and other factors.

As the discharge current increases, the battery capacity decreases. Accumulators with accelerated discharge modes give less capacity than those with longer discharging modes (small current). Therefore, batteries may be labeled at 3, 5, 6, 10, 20 and 100 hours of discharge. The capacity of the same battery will be completely different. The lowest capacity will be at a 3-hour discharge, the highest at a 100-hour discharge.

As the temperature of the electrolyte increases, the capacity increases, but at excessively high temperatures their life is reduced. This is because at higher temperature the electrolyte penetrates more easily into the pores of the active mass, as its viscosity decreases and the internal resistance increases. Therefore, more of the active mass takes part in the discharge reaction than when the charge was made at a lower temperature.

At low temperatures, however, the capacity and efficiency of the battery decrease rapidly.

750 mca to amp hours

For example, you need to translate 750 mca to amp hours.

To convert 750 nautical starting amperes (MCA) to ampere-hours (Ah), you will need additional information about battery capacity or discharge rate in Ah. Without this information, it is not possible to directly convert MCA to Ah.

Marine Cranking Amps (MCA) is a measurement used to determine a battery’s ability to start an engine in marine conditions. It represents the amperage that a battery can deliver at 32 degrees Fahrenheit (0 degrees Celsius) for 30 seconds while maintaining voltage above a specified level.

The ampere-hour (Ah), on the other hand, is a measure of a battery’s ability to deliver a certain amount of current over a certain period of time. It represents the total amount of charge a battery can give off in one hour.

If you provide the battery capacity in Ah or its rate of discharge, I can help you estimate the equivalent ampere hours based on the MCA rating.

What are cold start amplifiers?

Many batteries use CCA to represent the battery’s ability to start an engine at certain temperatures, usually between 30-32 degrees Fahrenheit. While knowing this initial capacity can help you choose the best battery, you will need to convert the CCA to AH to determine capacity.

CCA can be a good unit of measurement to help you determine the best battery for you if you live in cold conditions. Batteries with higher capacity and power will have better CCA values than weaker batteries. Even if the battery capacity deteriorates over time, they are more likely to last longer and provide better service.

Even though you can’t calculate battery capacity, you can still determine the best battery to replace.

Which battery should I choose?

Starting batteries are the most popular type of automotive battery and are used to start the engine and power various lighter loads (headlights, audio system, security system, etc.) with the engine off.

However, starting batteries should not be used for deep-cycle applications because their plates are relatively thin and have a large surface optimized for high-current applications.

Dual-purpose batteries cannot provide as strong starting currents as starter batteries, but they are much better at tolerating deep-cycle applications. Dual-purpose batteries are used both as starting batteries and to power various loads when the engine is off.

Dual-purpose batteries are very common industrial and marine batteries that are becoming increasingly popular, even in automobiles because of the increased power consumption during periods when the engine is off.

Deep-discharge batteries are optimized for deep discharge and cycling applications – they cannot provide high currents, but they cycle well.

Cold start current conversion table EN, CCA, SAE, IEC, DIN

CCA

Cold start amps describe a battery’s ability to provide the strong current needed to start/start internal combustion engines, usually within 30 seconds, and ampere-hours (Ah) describe a battery’s capacity and its ability to provide some current for typically 20 hours. CCA stands for Cold Cranking Amps, which is the cold start current of the starter battery. Cold cranking amps are measured in amperes using a special measurement technique. The following industry standards for Cold Start Current (CCA) measurements are distinguished:

SAE (JS537)/CCA

American standard (a fully charged battery is cooled to -0.4°F for 24 hours using the SAE JS537 technique. The battery is then loaded with a current equal to the battery’s CCA rating. The test is considered passed if the battery voltage does not drop below 7.2 V for 30 seconds).

EN (EN50342.1A1)

European Standard (a fully charged battery in accordance with the SAE JS537 technique is cooled to -0.4°F for 24 hours. The battery is then loaded with a current equal to the battery’s rated CCA. The test is considered passed if the battery voltage does not drop below 7.2 V for 10 seconds).

IEC (60095-1)

International Electrotechnical Commission (a fully charged battery is cooled down to -0.4°F for 24 hours in accordance with SAE method JS537. The battery is then loaded with a current equal to the battery’s CCA rating. The test is considered passed if the battery voltage does not drop below 8.4 V for 60 seconds).

DIN

German standard (a fully charged battery in accordance with the SAE JS537 procedure is refrigerated to -0.4°F for 24 hours. The battery is then loaded with a current equal to the battery’s rated CCA. The test is considered passed if the battery voltage does not drop below 9 V for 30 seconds and 6 V for 150 seconds).

JIS (D5301)

Japanese Industry Standard (A fully charged battery is cooled to 5°F for 24 hours using the SAE JS537 technique. The battery is then loaded with 150-300 amperes for 10-30 seconds. The test is considered passed if the battery voltage does not drop below 6V).

MCA (СА)

MCA (CA) – Marine standard (a fully charged battery in accordance with SAE JS537 technique is cooled to 32°F for 24 hours. The battery is then loaded with a current equal to the battery’s rated CCA. The test is considered passed if the battery voltage does not drop below 7.2 V for 30 seconds).

The following is a table of cold start current conversions (EN, CCA, SAE, IEC, DIN)

Cold Start Current (CCA) to Ampere Hours (Ah) Cross-reference table

The following reference table shows the average CCA and Ah values for starting batteries, dual purpose and deep cycle batteries for cars, RVs, marine, and light industrial batteries according to their BCI group:

Cold start current (CCA) is a value used to determine the ability of a battery to start an engine at low temperatures.

On average, the relationship between CCA and ampere-hours depends on battery type and averages:

• Lead-acid starting batteries: Capacity (Ah) x 10-16 = CCA (amps).
• Dual purpose lead-acid batteries: Capacity (Ah) x 8-12 = AAC (Amps)
• Deep cycle lead-acid batteries: Capacity (Ah) x 4-8 = CCA (Amps)

Many manufacturers limit the maximum amperage of their deep cycle batteries, emphasizing the fact that they are not designed for such use.

To check the actual capacity and CCA relationship, refer to the battery documentation and use these values as a guide only.

This means that starting a car engine in cold weather is much more difficult than in normal or warm conditions.

Therefore, you should pay attention to the CCA value of the battery if you live in colder regions, as a low CCA value can cause problems.

Therefore, batteries with a higher CCA rating will cause fewer problems when starting the car in colder regions.

In addition, you should be aware that as the battery ages, its CCA rating will gradually decrease. Therefore, you should replace it with a battery of the same or even higher capacity. Of course, you should choose the best car battery for cold weather.

Never buy a battery with a lower CCA rating if you live in cold regions.

Battery Diagnosis

If your car’s engine won’t start, you may have a bad battery. However, before you draw any conclusions, you should first check that the terminals are secure and that all connections are in the right places.

This way, you won’t have to accidentally replace a faulty battery. Whenever possible, be sure to clean the battery to prevent it from discharging.