Frequently Asked Questions

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No, but for ease of handling it is probably advisable.

Not advisable:

  • Batteries should be recharged at minimum of 10% of capacity. (E.G. a 100-ampere hour battery should be charged at 10 amps.)
  • When using an INTELLIGENT charger, the equalisation phase may go as high as 16 volts. (too high for AGM, and GEL batteries.
  • When charging a 12v 7.2 ampere hour AGM battery (gate motor/ alarm system) the amperage should be about 700 milliamps – 1 amp and in the equalisation phase should not exceed 14.7 volts.

Most battery chargers these days have polarity protection. If the battery is over discharged, the charger cannot read if the cables are connected correctly and WILL NOT charge. If this is the case, connect the charger to the flat battery and parallel a fully charged battery. See below. Switch the charger on. The charged battery will pull the current across the flat battery. After 10 – 15 minutes remove the fully charged battery.

NO. In cases such as this, you need to use a constant voltage charger. With INTELLIGENT chargers, each time there is a load placed on the battery, the charger will switch to the equalisation phase where the voltage is too high for continuous charging.

On automotive applications – 14.40 volts (maximum) if there is equipment that is used 24 hours a day such as mining equipment or the timber industry, then this voltage is TOO HIGH. Continuous charging should not exceed 13.8 volts – IN ANY APPLICATION.

DISCOVER & ENERTEC batteries, have a 12 – 18-month shelf life and WILL NOT GO FLAT on their own. There must be a current load to discharge these batteries.

NO. Batteries have specific criteria for application purposes. (E.G. Automotive, marine, standby, solar, deep cycle, golf cart, traction). The plate makes up is different and batteries must be applied correctly to ensure a reasonable life.

No, only deep cycle, high cycle and Discover batteries incorporating computer aided grid designs to optimise high power density may be used in frequent cyclic applications.

This is rather an open-ended question. In standby or cyclic application (UPS, emergency standby, fishing boat with accessories, golf cart, wheelchair etc.). Then the battery life is determined by the cycle life. The discharge and recharge is called a cycle and again is determined by the depth of discharge (10%, 20%, 30%) and the frequency. The bigger the depth of discharge and the higher the frequency, the shorter the life of the battery.

In lead acid batteries DEFINITELY NOT. As explained in (6) above, discharge and recharge are “LIFE OF THE BATTERY”. Batteries should be maintained at their optimum voltage and only used when it is necessary to do so.

The reason for this is what we call sulphation. Batteries have a self-discharge process over time and sulphation crystals form on the plates. The longer they are left discharged the worse the situation will be. If a battery is left discharged for long periods of time, the sulphation may become permanent and the battery will fail. Batteries should be recharged as quickly as possible after discharging and prior to storage.

This is what we term Parasitic loads. These loads have the worst effect on the battery as the discharge current is low and long. This results in the sulphate crystal forming very “perfectly” on the plates. Because the load is small and thus takes a long time for the battery to discharge, the battery is not charged frequently enough and through sulphation may cause premature failure. Another very good example is the two-way radios used on farmers bakkies and trucks. These radios are never switched off and the continuous small amp drain on the battery will result in a shorter service life. These should operate through a “switched relay” system, whereby the radio switches on and off when the ignition is switched on and off.

Definitely not. One battery tapped on a 24volt/ 36volt/ 48-volt system is resistance and will not allow the batteries to equalise. A simple step-down converter solves this problem whereby the system voltage 24/ 36/ 48 volts is fed in and the required 12 volts is fed out.

A dead cell may only be evaluated by means of testing equipment.

Voltage is not an indication of the capacity of the battery. It merely indicates that the battery is fully charged. The battery needs to be tested by means of a reliable electronic tester or a load tester.

When battery voltage is measured immediately after charging, the voltage reading may be higher than 13.0 volts. Either allow the battery to stand for six hours or, apply a load of 100 amps for 15 seconds allow the battery to rest for one minute then test again. If a battery has been standing overnight and the voltage is over 13.0 volts, then the battery has been overcharged.

  • Check the charging system on the vehicle
  • Check the battery charger that is being used (voltage regulated or not
  • A battery cannot “overcharge” itself. It is reliant upon the system in which it is operating and is not indicative of a faulty battery.
  • Weigh the battery and compare the weight against a new battery.
  • When a battery is overcharging, the excess gas escapes through the breather lessening the electrolyte level and thus making the battery lighter in weight.


Fire does not burn under water. If the battery were full, this could never have happened. The most common cause is an overcharged battery with seriously depleted electrolyte because of gassing. The plates become exposed and are surrounded by highly flammable hydrogen & oxygen. When a load is applied to the battery (like starting an engine) one of the plates may arc with another, igniting the gasses and causing an explosion.

Definitely not. When batteries are connected in series, a whole lot of criteria must be met.

  • The batteries must be the same make (identical technology)
  • The batteries must be the same capacity
  • The batteries must be exactly the same age

Batteries connected in series will never equalize one with the other should one or more batteries go out of sync. When one battery drops in voltage then all the other batteries nave to increase in voltage to carry the bad one. Overtime this potentially leads to the other batteries overcharging and thus failing prematurely.

The answer is again is NO for the same reasons given above. If one does replace the faulty battery, in time another will fail and then another and one will simply keep replacing batteries every few months.

The answer is NO. In a trucking application first check that there is not a 12-volt tapping of one battery for:

  • Two-way radios
  • Cell phone chargers
  • Coffee makers
  • TV, radio, etc.

If this is the case, then a 24 volt to 12-volt step down converter must be installed.

If one simply installs one new battery, there is every chance that the new battery will actually fail before the old battery. Electricity take the least line of resistance and a new battery has less resistance than an old battery and will therefore work harder and potentially fail sooner. Again, in is imperative that same make batteries, same ampere hour capacity and same age must be installed. It is better to use two older same age batteries that one new and one old battery.

For battery maintenance, the following are recommended:

Battery placement: Always use a well-ventilated area for UPS installation. The battery heats up during charging and operation. An airy place reduces the heating up of the battery. It also reduces the frequent water topping requirement.

Battery usage: After installation use battery on a regular basis. If the power cut does not occur, discharge the battery completely once every month and then recharge it. However, do not discharge the battery completely daily.

Water level check: Check the water level of battery every two months. Ensure that the water level is maintained between the maximum and minimum water limit. Always top up the battery with distilled water. Do not use tap water or rainwater as it contains excess minerals and impurities which affect the life and performance of the battery.

Cleanliness: Always keep the surface and sides of battery clean and dust free. Use cotton cloth to clean these surfaces.

Protection from rusting: Keep the battery terminals corrosion free and rust free. If the terminals get corroded pour hot water + baking soda solution on the corrosive area or use a toothbrush for cleaning. This will remove the corrosion. Once the terminals become corrosion free, apply petroleum jelly or Vaseline on to the terminals, nuts and bolts to avoid future corrosion. Rusting and corrosion are very bad for battery performance. Rusting in terminals reduces the current flow to and from the battery. This restricted flow of current results in slow battery charging which ultimately reduces battery life.

Open vents: Be careful that the vents around battery are dust free and open. Blocked vents lead to hydrogen gas accumulation which may lead to bursting of battery.

Safe installation: From safety point of view, install the UPS at safe places in your home which is out of the reach of children or a less used area. But at the same time make sure that it is airy and properly ventilated.

Battery replacement: Replace your battery if it is dead or damaged. Regular inspection will keep you updated on your inverter and battery conditions.


Yes and No. If the charger is a basic charger with no voltage regulation, then charge the flat battery overnight and then remove the battery and test it. Especially sealed batteries cannot be left connected permanently to unregulated chargers. It is advisable to use INTELLIGENT microprocessor-controlled battery chargers. They are inexpensive and may be left connected to the battery indefinitely. They also refresh the battery by de-sulphation and therefore add to the life of the battery.

Yes – unlike most AGM batteries the discover battery is very versatile and can be recharged with the vehicle charging system.

Yes- besides being a high-performance deep cycle battery discover has good cranking capabilities as well.

  1. Double Run time compared to wet flooded batteries
  2. Three times the life (i.e. 3000 cycles at 20% depth of discharge compared to 1000 cycles)
  3. Nonhazardous and fully compliant for Air, Sea, and road transportation
  4. Discover batteries perform at 30% above their rated capacity for 80% of their life cycle
  5. Wide range to choose from: 6-volt, 8-volt, 12-volt

The simple answer:

  1. Thicker plates
  2. Higher active material density
  3. High technology grid designs to optimize high power density
  4. Heavy duty plate straps
  5. Recombination gas technology
  6. Calcium / Calcium metal alloys
  7. Proprietary manufacturing techniques, additives and processes
  1. Double Run time in stationary applications compared to wet flooded batteries due to high voltage retention AGM technology
  2. Three times the life (i.e. 3000 cycles at 20% depth of discharge compared to 1000 cycles)
  3. Nonhazardous and fully compliant for Air, Sea, and road transportation
  4. Discover batteries perform at 30% above their rated capacity for 80% of their life cycle
  5. Wide range to choose from – 6-volt, 8-volt, 12 volts
  6. Produced and certified in ISO, QS and TUV facilities
  7. Lowest TOTAL COST OF OWNERSHIP when compared to other batteries
  8. Discover offers clean and green nonhazardous DRY CELL products

Yes – but the battery capacity and life will be reduced by 15%


The Homaya Solar Hybrid System is a back-up system that provides access to reliable electricity, and enables lesser grid consumption. It consists of a simple and reliable inverter that can take inputs from both the grid and solar. It comes in 2 variants:

  • Homaya Solar Hybrid System 850
  • Homaya Solar Hybrid System 1500

For System Sizing, steps are:

Choosing the HUPS

  • Calculate total load to be powered in watts. Multiply it by 1.67 to get effective load in VA.
  • Choose inverter size slightly greater than effective load in VA.

Choosing the battery size

  • Decide how many hours of backup do you want the system to provide.
  • Select battery voltage suitable for selected inverter. 12V and 24V for Homaya 850 and 1500 respectively.
  • Size of battery pack = (Total Watt load * Hours of backup required *1.9) / (Voltage of battery system) in Ah. · Add batteries in parallel to add Ah, add batteries in series to add voltage.
  • Only batteries of similar voltages can be added in parallel.

Choosing the solar panel

  • Voltage of panel is decided by the selected inverter. 12V and 24V for Homaya 850 and 1500 respectively.
  • Size of solar panel = (Total Watt load * Hours of backup required) / 3.


Sizing requirement

S.No Equipment Power Rating (Watts) Nos. Load Duty Cycle (Hours) Daily Energy Consumption (Watt Hours)
1 Fan 60 4 240 2 480
2 LED Light 10 3 30 2 60
3 Tubelight 40 3 120 2 240
4 TV 100 1 100 2 200
Total Load (Watts) 490 Daily Energy Consumption (Watt Hours) 980

UPS Sizing:

In the above example we are getting Sum of Loads = 490 watts Therefore UPS VA rating = 490 x 1.67 = 816.7 VA Therefore take 850 VA UPS which is close to the above calculated no. Note: Homaya 850 VA solar SHyS supports Battery Voltage of 12V and 30A Current rating.

Battery Sizing:

As the selected UPS supports 1 no. of 12V battery, hence use one 12V battery with this UPS. Battery Ah = (Total daily Watt-hours*1.9)/(12*Number of batteries) = (980*1.9)/12*1 = 155 AH. Hence choose a 150 Ah solar battery.

Panel Sizing for powering the load:

Panel size = Daily Energy Consumption in Watt -Hours/3 = 980/3 = 326.7 W. Since UPS supports 12V system, we need 12V panels say 100Wp or 150Wp. Hence install 3 x 100Wp panels in parallel or 2 x 150Wp panels in parallel.

The maximum solar panel wattage that can be connected is mentioned in the user manual. The specifics for the 850VA and the 1500 VA are as follows:

  • 850VA model: Upto 800 Wp with Voc of 17V to 21V
  • 1500VA model: Upto 1000Wp with Voc of 36V to 45V

Homaya 850 and 1500 can be operated till 25V and 50V on the PV side respectively. The SHyS is limited in taking inputs from the charge controller. Connecting anymore solar panel beyond the specified size does not yield any economic benefit to the customer. The SHyS however, is protected against the current rating of the solar panel. Overcurrent protection for solar power is rated at 40±3A for both Homaya 850 and 1500. The charge controller will automatically shut down after that with two auto-retries.

There is a built-in voltage regulator that holds voltages at 15V and 30V for Homaya 850 and 1500 respectively. However, exceeding 30V and 60V PV voltage can damage the PWM charge controller MOSFETs for 850 and 1500 respectively which are rated at the same. However, in a real scenario, a 24V panel will be pulled down to 12V when connected to a 12V battery during PWM charging with a loss in efficiency of the panels.

The load chart of a normal house is provided on the packaging box. The possible combination of loads for an 850VA system is as follows:

The possible combination of loads for an 1500VA system is as follows:

The recommended battery sizes for the Homaya Solar Hybrid System is 12V 100Ah- 200Ah and 24V 100Ah-200Ah for the 850VA & the 1500 VA models respectively. A minimum of 100Ah is required as the charging current is usually around 10A and higher.

The Homaya Solar Hyrbid system comes with the in-built protection against short circuit, overload, high temperature and internal fault. Further, it has resettable AC fuse and an inbuilt DC fuse.

The AC resettable fuse is rated at 10A and 15A for the 850VA and the 1500 VA model respectively. The AC resettable fuse has a life cycle of more than 500 cycles. However, if instant replacement on the field should be found, the datasheet is attached hereby.

The DC fuses protect the system against the reverse battery polarity and in other situations when the MOSFET inside the Homaya hybrid system get short-circuited. The battery reverse polarity occurs when the positive and negative terminals of the batteries are connected to the negative and positive terminals of the SHyS mistakenly. The 30A DC fuses are automotive DC fuses and can be found easily in many of the automobile distributors place. Take help from the nearest electrical installer to replace the DC fuse. The datasheet of the DC fuse is attached hereby.

The overhandling capacity of the 2 models are stated as below:

Overload in % Homaya 850 VA Homaya 1500 VA
110 4.5 min 4.5 min
120 1 min 1 min
150 10 sec 10 sec
200 1 sec 1 sec

The power factor of both the solar hybrid system is around 0.8. The maximum load at 0.8 power factor that can be connected to the 850 VA system is 680W and for the 1500VA system it’s 1200W.

The power saver mode and the i-charging mode are mutually exclusive of each other. The i-charging mode steps in when the power saver mode is OFF and vice-versa. The user can identify the mode in which the HUPS is operating by LED pictos in the display. The priority between solar and grid under different battery conditions is explained.

The Homaya SHyS is suitable for indoor application only. Product should be kept away from rain, sun and tough environmental conditions. However, the unit is IP21 and can stay rugged while in an indoor location.

Yes, presently the Homaya SHyS is compatible with all kinds of lead acid battery. It’s compatible with the tubular, flat plate or GEL-VRLA based lead acid battery.

Not recommended. The Homaya SHyS is not meant to be used with the other battery technologies. The inbuilt algorithm must undergo a change to accommodate other batteries, and can be done only if there is a sizeable demand order.

The 850VA model comes with a 12V 20A DC output where-as the 1500VA model comes with the 12V 5A DC output. The current output from the 850VA model is higher, as the 850VA model by itself is a 12V system

Homaya 1500 will display low battery condition if powered with a 12V battery and does not power the loads. If battery is connected while the system’s power battery is already in “ON” position, it will show low battery condition and a short circuit condition.

In 12V system, battery is electronically disconnected from the system at 17 ±0.5V. The 850VA system will beep every second with the “Mains charging” and “On battery” LEDs blinking when higher voltage is applied.

The product is powder coated on all the sides, hence the product can ideally sustain corrosion. However, appropriate preventive actions can be taken.

The Homaya SHyS comes with a warranty of 1 year. The system installer might increase the warranty based on the spares and tools available with him.

To start with, the spares provided with Homaya SHyS stands as this:

For the 850VA model

Spares’ component description
Application area
Approximate Quantity
(Will be adjusted as per costs during packaging)
PCB ASLY TSD RD732-07-850/220V 50HzAPC Main PCB250

For the 1500 VA model:

Spares’ component description
Application area
Approximate Quantity
(Will be adjusted as per costs during packaging)
PCB ASLY TSD RD732-06-1500VA24V R00 APCMain PCB250
PCB ASLY TSD L135-00 1500VA SOLAR H-UPSDisplay50

We can change the list of spares needed from the laundry list of spares as per attached later, with the cap being on the value. The value of the spares must be lesser than 2.5% of the order value

The Homaya SHyS will not turn ON. Once the product is connected with the correct polarities, the product starts functioning.

If AC fuse is tripped due to overload, “Mains Chg. LED” will be blinking and “On Mains LED” will be on. Press (1) as shown in Fig 1 to reset AC fuse.

The following document has a log of indications and alarms present in Homaya SHyS.

S.NoPARAMETERSHomaya 850Homaya 1500
  1. Ensure that the mains connection (3) of the inverter is not connected before working on the connections of the Homaya HUPS. Turn off the main MCB of the house before starting connections.
  2. Select relevant battery type (Tubular, Flat Plate,Gel/VRLA) using the battery selector switch (6) and keep i-Charge off (8) from the back panel.
  3. For Homaya 850, connect Red cable labelled with a “battery +” (4) symbol from the HUPS to the positive terminal of the battery and the black cable labelled with a “battery -” (5) symbol to the negative terminal of the battery. For Homaya 1500, connect negative of first battery to the positive of the second battery. Connect Red cable labelled with a “battery +” (4) symbol from the HUPS to the positive terminal of the first battery. Connect the black cable labelled with a “battery -” (5) symbol to the negative terminal of the second battery.
  4. Tighten all bolts securely from the battery terminals.
  5. Connect the positive cable from the solar panels to the terminal at the back panel of the HUPS labeled PV + (left side part of 9) and negative cable of the solar panel to the terminal labeled PV – (right side part of 9).
  6. Connect a well-fitting electrical plug into output socket (2). Right pin of output socket is Live wire, labeled “L” and should be connected to an external MCB before connecting to load. “N” need not be connected. Live wire from the grid should not be connected to the live wire of the output socket or to the load. Only live wire from the HUPS should be connected to load with a common neutral wire.
  7. Connect Input cable (3) to any power socket in the house.
  8. Connect DC Load wires to DC load terminals (10). Left side of (10) is positive and right side of (10) is negative.
  9. Turn on the power for Input cable and turn on the HUPS by pressing power button. Turn mains and load MCB on. Select ECO and UPS as required (7).

Fig 2. Connection Diagram for Homaya 850

Fig 3. Connection Diagram for Homaya 1500


Active Material: This refers to the positive and negative plate pastes that provide energy from a battery when it is discharged. For a lead-acid battery, the positive active material, or PAM, is lead dioxide; the negative active material, or NAM, is sponge lead.

Ampere-hour: The value is used to define the capacity of the battery. It is current in amperes, multiplied by the time in hours, during which current flows from the battery.

Available Capacity: The capacity available from the battery based on its state of charge, rate of discharge, ambient temperature and specified cut-off voltage.

Capacity: The electrical energy available from a cell or battery expressed in ampere-hours. It refers to the discharge of a constant current in a specified time to a specified cut-off voltage (normally 1.75V /2V cell) at a specified temperature.

Capacity Recovery: Also called recoverable capacity. This is the discharge capacity that can be restored to a cell or battery through various treatments when it has dropped to very low capacity levels.

Cell: The minimum unit of the battery. The nominal voltage of a cell of the Lead-Acid Battery is 2.0V. Most batteries are made of 2 or more cells. Typically 3 cells for a 6Volt, and 6 cells for a 12Volt battery.

Charge: The process of restoring electrical energy to a cell or battery, in the process increasing the cell voltage.

Charge Efficiency: Ratio of the ampere-hours delivered during discharge divided by the ampere-hours put into the battery during recharge.

Constant Voltage Charge: One of the charge methods which uses voltage limitation. When the discharged battery is charged by this way, the charge current is reduced automatically according to the state of charge. This is the most recommended charge method for VRLA batteries.

Constant Current Charge: One of the charge methods which uses current limitation. According to the charge time, some fixed amount of capacity is charged. Therefore this charge method requires the presence of devices which prevent overcharge such as a timer etc., for VRLA battery.

Cut-off Voltage: The final voltage of a cell or battery at the end of charge or discharge.

Cycle: A single charge and discharge of a cell or battery.

Cycle Life: The number of cycles a cell or battery provides before failure.

Cycle Use: A method of using a secondary battery repeatedly by charging and discharging.

Deep Discharge: The discharge of a cell or battery to 80-100% of its rated capacity.

Depth of Discharge: Frequently expressed as a percentage. It is the amount of capacity removed from a cell or battery during discharge.

Discharge: The function of removing current from a cell or battery.

Discharge Rate: Normally expressed as a fraction of C: it is the rate at which current is taken from a cell or battery.

Discharge Voltage: The closed circuit voltage of a battery during discharge.

Electrode: The positive or negative plate holding the active materials in the cell.

Electrolyte: Conducts ions in the cell. Lead-Acid Batteries use sulphuric acid solution.

Float: Maintains full capacity in a cell or battery by applying a continuous charge. In this instance, the load is connected to the battery and current is provided from the charger.

Gelled Electrolyte: Refers to a type of VRLA cell or battery where the electrolyte is immobilized in a gel made from fumed silica, said gel then contained within a coarse glass mat or microporous separator matrix. This gel mat serves as the separator in the VRLA cell in place of the more common glass microfiber material.

High-rate Charge/Discharge: Charge / discharge processes that are carried out at relatively high current densities, with the multiple of C rate depending upon the battery design.

Internal Impedance/Resistance: A measure of a cell’s electrical resistance to current flow, resulting in small or large voltage drops and some level of resistive heating. Impedance (AC) and resistance (DC) values are proportional but different, resulting from differences in measurement methodology.

Internal Short Circuit: Positive plates and negative plates touch inside of the cell.

Life: The maximum time period battery can longer be used before it loses its characteristics.

Load: A device or mechanism external to a battery, and which is powered by the battery. The resistance of the load and the battery voltage dictate the current flow rate, and thus the run time for the battery.

Maintenance-Free: Secondary cells that are not sealed require periodic addition of water. Sealed Lead-Acid Batteries do not require such maintenance. Therefore, they are called “maintenance free”.

Nominal Voltage: A nominal value to be used to indicate the battery voltage; for the Sealed Lead-Acid Battery; the nominal voltage is 2V / cell.

Open-Circuit Voltage: The measured voltage of the cell or battery without a load attached.

Overcharge: The continuous charging of a cell after it achieves 100% of capacity. The battery life is reduced by prolonged over charge.

Overcharge Current: The charge current supplied during overcharge. Batteries can accept continuous overcharge at recommended rates and temperatures.

Quick Rechargeability: The ability of quick charge acceptance of the batteries. Quick recharge requires not only good charge acceptability but also safety devices such as thermostat, timers, etc.

Rated Capacity: The manufacture’s rated capacity of the cell (see capacity).

Refresh Charge: A recovery charge which is done periodically for recovering the lost capacity of batteries due to self-discharge.

Secondary Battery: A battery that can be charged and discharged repeatedly. Example: Lead-Acid Batteries, Nickel Cadmium batteries.

Self-Discharge: The loss of capacity by a battery while in the stored or unused condition. The rate of self-discharge is affected by ambient temperature.

Separator: The material separating the electrodes. Used to hold the electrolyte. Normally glass fibre is used.

Shelf Life: The life of a battery when stored in the unused condition.

Stand-by Use: A method of using secondary batteries in which the battery is constantly charged so that it is always ready for use.

UL: Term for Underwriters’ Laboratories, a standards and testing agency for batteries that may be used in consumer applications in the U.S. There are a large number of standards for various consumer devices and anyone wishing to have batteries in these devices must first obtain UL approval.

UPS: Uninterruptible Power Supply.

Undercharging: This is a situation where the charge put back into a battery after a discharge is not sufficient to fully charge it, given a certain amount of overcharge necessary for the product. It leads to rapid loss of capacity in cyclic duty and on float using too low a charge voltage can actually result in partial discharge of one or both plates during charge. Because of the tendency to treat them too delicately, undercharging is a common source of VRLA battery failure.

Valve-regulated (Cell or Battery): Term for a lead-acid battery employing oxygen recombination technology, either glass mat or gelled electrolyte, and which contains a pressure-relief valve to vent gases, primarily on overcharge. Common usage acronym is “VRLA”, standing for Valve-Regulated Lead-Acid. Formerly called sealed lead-acid, SLA.

Vent: Pressure-relief valve in a cell or battery that allows for the escape of gases at some release pressure but does not allow any level of gas ingress.

VRLA: Valve Regulated Lead-Acid.Car battery: A car battery is a plastic box divided into six cells that is filled with an electrically conductive sulphuric acid solution called an electrolyte. This chemical interacts with the battery's electrodes, or metal plates containing lead and lead oxide, to produce 12 volts of electricity. The car battery has three basic tasks. First, it provides the initial power to start the engine of a car. Second, it keeps itself recharged and generates power when the car's engine is not running. Lastly, it can maintain a low current to power the lights, horn and other electrical devices for a short period.

CCA : The rating used to define a battery's ability to start an engine in cold temperatures is called Cold Cranking Amperage (CCA). The CCA of an auto battery is the amount of current a given battery can deliver for 30 seconds at 0 °F (-18 °C) without dropping below 7.2 volts for a 12-volt battery. To find the power of a car battery we multiply the CCA number by 7.2 volts. For example,

  • P = IV
  • P = (600 A) (7.2 V)
  • P = 4320 W
  • Most modern cars require relatively low cold cranking amps that range from 400 to 600. Sports cars and light trucks require higher cranking amps ranging from 700 to 1000 A.