Capacity Ratings

The battery must be capable of cranking the engine and providing adequate reserve capacity. Its capacity is the amount of electrical energy the battery can deliver when fully charged. Capacity is determined by the size and number of plates, the number of cells, and the strength and volume of electrolyte.

The most commonly used ratings are:

• Cold Cranking Amperes (CCA)

COLD-CRANKING AMPERES (CCA)

The battery's primary function is to provide energy to crank the engine during starting. This requires a large discharge in a short time. The CCA Rating specifies, in amperes, the discharge load a fully charged battery at 0°F (-1 7.8°C) can deliver for 30 seconds while maintaining a voltage of at least 1.2 volts per cell (7.2 volts total for a 12-volt battery). Batteries used on various Toyota vehicles have CCA ratings ranging from 350 to 560 amps.

RESERVE CAPACITY (RC)

The battery must provide emergency energy for ignition, lights, and accessories if the vehicle's charging system fails. This requires adequate capacity at normal temperatures for a certain amount of time. The RC Rating specifies, in minutes, the length of time a fully charged battery at 80°F (26.7'C) can be discharged at 25 amps while maintaining a voltage of at least 1.75 volts per cell (10.5 volts total for a 12-volt battery). Batteries used on various Toyota vehicles have RC ratings ranging from 55 to 115 minutes.

AMP-HOURS (AH)

The battery must maintain active materials on its plates and adequate lasting power under light-load conditions. This method of rating batteries is also called the 20-hour discharge rating. Original equipment batteries are rated in amp-hours. The ratings of these batteries are listed in the parts microfiche. The Amp-Hour Rating specifies, in amphours, the current the battery can provide for 20 hours at 80°F (26.7°C) while maintaining a voltage of at least 1.75 volts per cell (10.5 volts total for a 12-volt battery). For example, a battery that can deliver 4 amps for 20 hours is rated at 80 amp-hours (4 x 20 = 80). Batteries used on various Toyota vehicles have AH ratings ranging from 40 to 80 amp-hours.

POWER (WATTS)

The battery's available cranking power may also be measured in watts. The Power Rating, in watts, is determined by multiplying the current available by the battery voltage at 0°F (-1 7.8°C). Batteries used on various Toyota vehicles have power ratings ranging from 2000 to 4000 watts.

TYPICAL TOYOTA ORIGINAL-EQUIPMENT BATTERIES

Battery

Rating

50 D 20 55 D 23 N 70 Z

50 Amp-Hours 60 Amp-Hours 70 Amp-Hours

REPLACEMENT BATTERIES USED ON TOYOTA VEHICLES

BCI GROUP* (DIMENSIONS)

TYPE (MONTHS)

PLATES (NUMBER)

RATINGS

CCA (AMPERES)

RC (MINUTES)

24, 24F

(10-3/16Lx 6-3/16Wx9H)

24

48

350

55

36

54

400

60

48

72

525

( 12L x 6-3/16Wx 8-15/16H)

48

84

560

115

FACTORS AFFECTING CHARGING

Five factors affect battery charging by increasing its internal resistance and CEMF (counter-electromotive force produced by the electrochemical reaction):

1. TEMPERATURE: As the temperature decreases the electrolyte resists charging. A cold battery will take more time to charge; a warm battery, less time. Never attempt to charge a frozen battery.

2. STATE-OF-CHARGE: The condition of the battery's active materials will affect charging. A battery that is severely discharged will have hard sulfate crystals on its plates. The vehicle's charging system may charge at too high of a rate to remove such sulfates.

3. PLATE AREA: Small plates are charged faster than large plates. When sulfation covers most of the plate area, the charging system may not be able to restore the battery.

4. IMPURITIES: Dirt and other impurities in the electrolyte increase charging difficulty.

5. GASSING: Hydrogen and oxygen bubbles form at the plates during charging. As these bubble out, they wash away active material, cause water loss, and increase charging difficulty.

Capacity Control SystemArbeitsblatt Mohammed
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Responses

  • antje
    Why toyota Corolla batter ampair?
    1 year ago

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