Starter battery

from Wikipedia, the free encyclopedia

Car battery with a voltage of 12 V and a capacity of 36 Ah. Earlier, open version with block lid, transparent housing, central degassing and the option of refilling with distilled water after unscrewing the six round stoppers.

The starter battery , when the motor vehicle as a car battery or car battery referred to is an accumulator , inter alia, the electric power for the starter motor of an internal combustion engine provides, for example, in motor vehicles , generator sets or gas turbine of an aircraft. Lead-acid batteries are often used as starter batteries .

An accumulator, which is used not only for starting, but also as an energy source for driving an electric vehicle , for example in electric cars or hybrid vehicles , is called a drive or traction battery . To increase the security against unintentional discharge, these vehicles often have a further accumulator in addition to the drive battery to supply the on- board network .

Batteries in automobiles and ships

The starter battery fulfills various tasks in the motor vehicle:

  1. It supplies relevant assemblies with voltage before starting (control units, injection system, ignition coil, glow plug system).
  2. It supplies the starter motor ( starter ) with energy.
  3. It supplies the vehicle's emergency lighting (lights, hazard warning lights) even when the engine is not running.
  4. It smooths the alternator voltage and reduces voltage peaks in regular driving.
  5. When the vehicle is stationary, it supplies various consumers with energy (clock, radio, control unit).

As soon as the engine is running, the alternator takes over the voltage supply of the system and charges the starter battery again. (Engl. After consumers starter, lighting and ignition ignition ) starter batteries are also referred to with the acronym as SLI battery.

Starting an internal combustion engine using the electric starter engine briefly requires currents of several hundred up to 1000  amperes . The car start process takes two to fifteen seconds for well-maintained engines and up to one hundred seconds for older vehicles. The battery loses up to around 0.2 Ah in the case of a petrol engine (with a start time of 2 seconds) and up to around 0.3 - 0.4 Ah in the case of a diesel engine (7 seconds start time with preheating). About 3–5 minutes (travel time) are required to recharge the battery capacity of 0.2 Ah that has resulted from this. The starter battery must be able to deliver the current strength even at low winter temperatures. Since the electrical voltage must not drop too much during the starting process, starter batteries have a low electrical internal resistance .

Car and truck starter batteries differ in their capacity and thus also in weight and dimensions.

In trucks, the voltage of the on-board network is usually 24 V instead of 12 V. In most cases, two 12-volt batteries of the same type are used in series or, more rarely, 24-volt batteries with twice the number of cells.

In cars with automatic start-stop systems , the usual starter batteries are quickly overwhelmed, since the significantly more frequent starting processes require increased cycle stability of the accumulators. EFB ( Enhanced Flooded Battery ) batteries containing fleece mats have been developed for pure start-stop operation (without recuperation ) .

The VRLA or AGM ( Absorbent Glass Mat ) accumulators, which have been used in standby mode and for small drives for around 50 years, have also been further developed into starter batteries. These are used for vehicles with a start-stop system and recuperation technology. With these, a generator is driven when braking, which charges the accumulator. AGM accumulators allow up to four times the number of charging cycles compared to conventional batteries. The design-related low internal resistance also promotes a quick reaction between the acid and the plates, which means that high amounts of energy can be absorbed quickly. The expensive AGM accumulators are susceptible to increased temperatures, which is why they are often not installed in the engine compartment, but in the interior or in the trunk.

Accumulators using other redox systems, e.g. B. a lithium technology , could not prevail against lead-acid batteries for reasons of cost. These accumulators also require complicated charging and protection circuits. The weight savings are not high enough to justify use in large-scale production. Only Porsche offers LiFePO 4 batteries as starter batteries for a surcharge . In the retrofit business, occasional scooter and motorcycle riders use batteries with lithium systems.

Batteries in aircraft

Compared to other battery technologies, the inexpensive lead-acid battery is comparatively heavy. In aircraft, therefore, nickel-cadmium accumulators , increasingly also nickel-metal hydride accumulators , silver-zinc accumulators and lithium-ion accumulators are used as starter batteries for starting piston engines or auxiliary turbines .

Construction and handling

Different arrangements of the poles on a starter battery

Starter batteries usually contain a series connection of lead accumulator cells, each of which has a nominal voltage of 2 V. In order to achieve a nominal voltage of 6 V or 12 V or 24 V, three, six or twelve cells are connected in series. Depending on the nature of the electrolyte , lead batteries are divided into wet cells and fleece and gel batteries ( VRLA batteries ).

The positive pole of starter batteries is often marked with a plus sign and the color red, the negative pole with a minus sign and the color black or blue. To avoid confusion, the poles have different diameters. In most vehicles, the negative pole is a ground pole that is electrically connected to the vehicle body. However, some older English and US vehicles use the positive pole as the vehicle ground.

The starter battery is connected to the vehicle's electrical system via the pole terminals . Incorrect connection ( reverse polarity ) of the battery can result in serious damage to the vehicle's electrical system.

The position of the plus and minus pole of a starter battery depends on the model. The so-called pole arrangement describes the position of the battery poles when looking at a battery from the front. In Germany, a numerical scheme is used to name the pole arrangement. The following applies to 12 volt starter batteries:

Pole arrangement plus minus
0 right front left front
1 left front right front
2 right front left rear
3 left rear left front
4th left front left rear

Jump start

The correct polarity must also be observed when starting aid by connecting a charged starter battery in parallel in order to avoid overvoltage (24 V) in the connected vehicle electrical system. Failure to observe this usually leads to damage to the control units. It is recommended to connect the negative pole of the supporting battery to the engine block or a point on the body further away from the vehicle battery in order to avoid high equalizing currents between the batteries.

To prevent a short circuit to the vehicle ground when changing the battery or handling tools (risk of fire and burns!), The negative pole should always be disconnected first and connected last. The positive pole is often covered to prevent a short circuit in the event of a traffic accident or incorrect operation.

Problems and Treatment Options

The following sections refer specifically to lead-acid batteries unless otherwise stated .

Acid and heavy metal

The electrodes are made of lead or lead compounds and are therefore poisonous . The 37 percent sulfuric acid contained as an electrolyte is highly corrosive . Protective equipment must be used to prevent the acid from coming into contact with the skin. Acid should be washed off the skin immediately with plenty of water. After acid splashes on textiles, holes usually form in the fabric after a few hours.

To ensure that the lead can be reused and the acid it is disposed of, a deposit is paid out in Germany when lead batteries are returned to the dealer.

Temperature dependence of the capacity

The deeper a (starter) battery has cooled down, the higher its output resistance or its internal resistance. Due to the increased electr. Resistance, the voltage drop increases under the same load, so that a lower usable power capacity is available. At −18 ° C less than half of the normal capacity is available. At extreme temperatures, the recommendation is to remove the accumulator and store it overnight in a heated room.

Since starting the engine requires more power in winter, due to the more viscous engine oil , it can be advisable, especially with older batteries, to check before the onset of winter whether the remaining capacity is still sufficient for starting at low temperatures. In older batteries, the individual cells were usually accessible after unscrewing a stopper in order to check the acid density with an acid siphon and to top up with distilled water if necessary.

In the case of closed batteries with wet cells, the remaining capacity can be estimated using the open circuit voltage of the starter battery. If the battery is well charged, it should still be more than 12.7 V a few hours after the charging process is complete.

Sludge formation and grid corrosion

The charging and discharging processes during operation ensure that the lead is converted into lead dioxide or lead sulfate . This leads to the gradual loosening of the lead plates, the formation of sediment ( lead sludge ) and an increasing loss of capacity. This is known colloquially as silting up the cells. At the bottom of starter batteries with liquid electrolytes there used to be troughs in which the "sludge" collected. If the sediment ultimately the plates (electrodes) was touched a cell conclusion of the cells. The accumulator was then also referred to as “slipped together”. Nowadays pocket separators, with which a plate (either plus or minus) is alternately completely enclosed, prevent sludging. Modern batteries no longer have a mud chamber, the electrodes are directly on the bottom of the housing. Furthermore, the positive lead grids are gradually converted into lead dioxide over the course of their useful life. This so-called grid corrosion leads to interruptions in the current arrester and thus to cell failure.


The electromechanical charge regulators with inaccurate voltage regulators or unregulated or overly powerful chargers , which were in use until the 1970s , often led to the cells being overcharged. When charging, all of the lead sulfate is first converted back into lead (negative electrode) and lead dioxide (positive electrode). If the charging current continues to flow after the end of charge voltage has been reached, the lead of the grid is attacked (grid corrosion). In addition to the formation of oxyhydrogen, the grid becomes larger and the strength of the pressed-in substances decreases.

Charging voltage and "outgassing"

Automatic battery charger for a 12 V starter battery

The end-of- charge voltage should be between 15 and 25 ° C for the 12 V starter battery, depending on the battery type, in the range of 13.8 to 14.8 V. The charging current in amperes should be one tenth of the battery capacity in ampere hours (e.g. 4 A for a battery with a capacity of 40 Ah) in order to achieve a long service life. With fast charging, the charging current should not exceed a third of the value of the capacity. In motor vehicles, the alternator regulator also regulates the end-of-charge voltage (approx. 14 V), which is why a higher charging current often flows after the engine has started, depending on the state of discharge.

If the charging voltage is above 2.4 V per cell (with a 12-volt battery that is a total of 14.4 V), grid corrosion begins, which is noticeable through the audible formation of gas bubbles in the battery. To prevent this, the accumulator should not be charged with high currents until it is fully charged. A quick charger should only charge a discharged lead-acid battery up to approx. 70% of the capacity and then switch to a lower charging current. Just like the automotive alternator regulator, chargers should have a voltage limiter that interrupts the charging process when charging rapidly at 14.4 V (or up to 14.8 V for AGM batteries) and when charging continuously at 13.8 V. The permanent or trickle charge is used for example in emergency generators. The cell voltage is limited to 2.3 V or 13.8 V for a 12-volt battery.

Risk of explosion

Overcharging leads to " gassing " of the starter battery. Gassing is the electrolytic decomposition of the water that is contained in the dilute sulfuric acid. This creates oxygen and hydrogen , which together form highly explosive oxyhydrogen . Therefore, avoid sparks, naked lights and hot or glowing objects in the vicinity of accumulators.

Acid level

It used to be common to check the fluid levels of the cells regularly. If the liquid level can be seen from the outside through the housing material, this should be checked occasionally, even with maintenance-free accumulators. The liquid should be about 10 mm above the top of the plate. If the acid no longer covers the plates, the zone that has fallen dry will be damaged. Only demineralized or distilled water may be used for refilling .

With current, maintenance-free accumulators, the cell covers can no longer be easily removed, and it is usually hardly possible to close them tightly again.

Too little charge

Far more common than these errors is insufficient battery charge. Modern vehicles draw energy from the battery even when they are stationary (control unit, clock, radio, etc.). The battery loses around 0.5 Ah per day, 3.4 Ah per week and at least 15 Ah per month if it is not used.

In addition, in winter, when the performance of the accumulators is limited by low temperatures, additional consumers (heated seats and windows, frequent driving with lights, etc.) are used. This can result in the alternator no longer being able to fully recharge the starter battery during operation, especially when driving frequently over short distances.

If the lights (or another large consumer) are accidentally left on in a parked vehicle, the battery can discharge excessively in a short period of time. In such cases, a sufficiently high charge level must be restored by so-called " bridging " (see also starting help ).

Stand damage

If a car has not been used, one is damage to property by a self-discharged battery possible. Lead sulfate is formed on both plates. At first, like the starting materials, it appears in powder form, but it is tiny crystals . These have a large surface area that allows a quick response when loading. But they have the unpleasant quality that they grow together. If the battery is left idle for a long time with low voltage, large and hard crystals form. On the one hand, these have a comparatively small surface area, which is synonymous with lower capacity , and, on the other hand, they can hardly be destroyed by charging. That means a greater loss of capacity. In this case one speaks of “coarse crystalline sulphation ”. It ultimately leads to the total failure of the accumulator. In the case of vehicles used seasonally, such as two-wheelers, mobile homes, motor boats, snowmobiles, etc., these problems are likely after a long period of non-use.

Maintenance, care and testing

Battery tester for simple testing of starter batteries when installed and removed. Evaluation of internal resistance, current charging voltage in volts, state of charge in percent and maximum possible (cold) starting current (CCA / CA) in amps.
  • Before winter, the liquid level (or electrolyte ) should be checked in wet cells . If it is too deep, the accumulator must be filled up to the mark with demineralized water . Maintenance-free accumulators, whose cells can no longer be opened and whose electrolyte cannot be refilled, have been established since the 2000s. These accumulators are designed in such a way that the decomposition of the electrolyte into hydrogen and oxygen is minimized. Unclean water, including tap and mineral water in this case, would render the accumulator unusable within a short time (corrosion of the electrodes). Badly working voltage regulators of the alternator favor the decomposition of the water and require more maintenance.
  • Check of the controller by a specialist workshop for charging voltage and charging current. The charging voltage must be at least 14.4 V and should not exceed 15.4 V (wet cells) and 14.8 V (AGM). If the charging voltage is too high, even maintenance-free batteries quickly lose too much water, which has a negative effect on their service life. If the voltage is lower, the accumulator is not fully charged, which makes the following starting processes more difficult and shortens the service life.
  • Chargers should work with at least 14.8 V in the upper charging range, and the charging current for unregulated chargers should not exceed one tenth of the capacity of the battery divided by 1 hour. When the battery is deeply discharged, rapid charging with high currents is possible up to approx. 70 percent of the full charge, but the voltage must not exceed 14.4 V here either.
  • The accumulator should be checked after charging. Among other things, the acid density when fully charged must be observed. Various systems are available on the market. The acid density can be determined by means of a hydrometer , also known as a spindle, acid siphon or with terms like the magic eye , or alternatively by means of a refractometer .
state of charge
1.28 g / cm³ > 12.8V fully charged (100%)
1.22 g / cm³ approx. 12.6 V. normally charged ( 070%)
1.18 g / cm³ approx. 12.4 V. weakly charged ( 050%)
1.12 g / cm³ approx. 12.0 V. normally discharged ( 020%)
1.06 g / cm³ <11.8V discharged and deeply discharged ( 000%)

The most common density of 1.28 g / cm³ when fully charged is assumed here as an example: When fully discharged, the density has dropped to 1.06 g / cm³, at 1.20 g / cm³ the battery is only half charged. If you work with a hydrometer, you get a good overview of the state of charge, but you have to open the cells and suck in a sample of the electrolyte. This is only recommended if you have sufficient experience.

Another possibility is to measure the battery voltage in the idle state (idle voltage). No disassembly is required for this. Most devices are simply connected to the starter battery. It should be noted that this measurement can only be carried out when the accumulator has calmed down, i. H. about 2 hours after the last charge / ride / discharge. A calm accumulator shows a voltage of 12.65 V when fully charged.

The voltage should not drop below 12.6 V, which is approx. 70% of the full charge. At 12.4 V the accumulator is half charged, at 11.8 V it is discharged. Should it continue to be discharged, it can only regain its original capacity if it is charged immediately.

The method only provides a reasonably usable information if the battery has not become high-resistance. A high-resistance accumulator can be recognized by the fact that it is "full" very quickly when charging, but the voltage immediately collapses again, even when small currents are drawn. If, on the other hand, the starter battery is still OK, it should be able to deliver roughly three times its nominal capacity / 1h of current for a few seconds without any problems and without the voltage dropping too much.

Starter batteries should not be left standing for long periods (several months) without a sufficient charge . If an accumulator has to stand still for a long time, it should be fully charged beforehand. Older starter batteries have an increased self-discharge , and if the starter battery is left standing without recharging there is an increased risk of harmful sulphation . Leaving it to stand for too long therefore damages the accumulator. A starter battery can be stored unused for 12-15 months after a full charge. The voltage of a 12-volt lead-acid battery should generally not drop below 11.8 V and not below 12.7 V for a longer period of time.

If the device is not used for a long time, a so-called trickle charge with a low voltage of 13 - 13.4 V is helpful, with a low current that only compensates for self-discharge .

Voltage values ​​on starter batteries for operating charging, recharging, maintenance charging and capacity control

The charging voltage should be around 15 ° C to 25 ° C in the range of 14.8 V (AGM) to 15.4 V. The charging current for unregulated chargers should be a tenth to a maximum of a fifth of the battery capacity / 1h and not exceed a third of the value of the capacity / 1h even with fast charging. A limitation of the charging current is not necessary for voltage-regulated chargers.

The gassing voltage is around 15.8 V and should not be exceeded, especially when charging sealed starter batteries. The terminal voltage shortly after the end of the charging of a starter battery that has just been fully charged will first drop rapidly from the charging voltage to around 13.2 V and from then on more slowly to around 12.8 V.

Another problem that can discharge the starter battery is leakage currents . This can happen if the surface of the battery or the poles are dirty (for example due to environmental influences such as dirt and moisture).

Corroded connections lead to increased contact resistance and have a negative effect on starting behavior. They also prevent the generator from fully charging the battery. Care should be taken to ensure that the connections are clean and that the contact surfaces are firmly connected to the terminals of the battery. The use of pole grease also provides protection against corrosion .

Low-maintenance, maintenance-free and MF batteries (VRLA)

designation Specific water consumption
Low maintenance accumulator Maximum 16 g per Ah nominal capacity after 42 days
Maintenance-free - cool installation location Maximum 03 g per Ah nominal capacity after 42 days
Maintenance-free - hot installation location Maximum 08 g per Ah nominal capacity after 42 days

An accumulator is called “low-maintenance” if the total water consumption determined after 42 days is a maximum of 16 g / Ah of the nominal capacity . Low-maintenance accumulators are no longer manufactured today.

An accumulator is called "maintenance-free" if, under normal circumstances, no distilled water has to be refilled (see table below).

Maintenance- free, sealed VRLA accumulators , also known as MF accumulators, have been on the market since around the 1990s . MF stands for English Maintenance Free . From the 2000s onwards, they almost displaced the classic lead-acid accumulator with the colored plugs on the top and the ventilation hose attached to the side. Such a battery can be six or seven years old with good care. The »maintenance-free« therefore mainly refers to the fact that no distilled water has to be refilled, because little disappears from it.

VRLA accumulators have a fixed electrolyte. The cell plugs cannot be unscrewed. The gases hydrogen and oxygen produced during overcharging are converted back into water within the respective cell. In the inaccessible sealing plugs there are degassing valves, which enable a targeted gas discharge into the central degassing channel in the event of excess pressure. In addition, there is a ceramic filter under the cover on the safety valve, which serves as protection against ignition or explosion.


  • Maintenance-free, as there is no need to check the electrolyte (sulfuric acid) or top up with distilled or demineralized water.
  • Can be used in any position (AGM and gel battery).


  • If the charging is too strong, the excess gas escapes through a degassing valve. Since these amounts of liquid cannot be replaced, permanent damage to the battery is possible.

Additional note: With central degassing , the gas emerges from the battery at a defined point. With the help of a degassing hose, the discharge of the gas can take place specifically to a non-critical side z. B. away from ignition-carrying parts. Depending on the installation location, the battery can degas on the positive or negative side. A backfire inhibitor is usually provided, consisting of a porous plastic disc, the so-called frit. This is located in front of the opening of the central degassing. If the gases emerging from the venting opening are ignited from the outside, the frit is intended to prevent the flame from penetrating the inside of the battery.

Abbreviations and terms

Starting current, CA

The starting current indicates the maximum current that the starter battery can deliver at 0 ° C for a period of 30 s, at which each individual cell still has a voltage of 1.2 V. The English technical term for starting current is cranking amps , from which the abbreviation CA is derived. This information is also known as MCA (short for marine cranking amps ).

Cold start current, CCA

The cold start current indicates the maximum current that the accumulator can deliver at −18 ° C for a period of 30 s. Each individual cell still has a voltage of 1.2 V (according to the American standard SAE ). According to the German Institute for Standardization ( DIN ), the total voltage of a 12-volt battery should still be 9 V or 1.5 V per cell after 30 s.

The technical term for cold start current is cold cranking amps , from which the abbreviation CCA is derived. The cold start current of car starter batteries is usually between 200 and 850 A, with the most common accumulators being between 360 A and 680 A. Trucks have starter batteries with a higher cold start amperage between 500 A and 1200 A.

Warm start current, HCA

The warm start current (HCA) indicates the maximum current output in amperes at a temperature of 26.7 ° C and a duration of 30 s. The voltage per cell of the battery must not fall below 1.2 V, i.e. the total voltage must not fall below 7.2 V. The English technical term for warm start current is English hot cranking amps , from which the abbreviation HCA is derived.

Reserve capacity, RCM / RC

The reserve capacity indicates the amount of charge that a battery can deliver with a load of 25 A up to the final discharge voltage of 10.5 V. This value corresponds to the actual capacity of the battery. It can deviate considerably from the nominal capacity, especially with old batteries. The reserve capacity can be determined relatively precisely using modern measuring methods such as electrochemical impedance spectroscopy "EIS".

Battery size, BCI and weight

Due to the variety of motor vehicles with internal combustion engines, there are a large number of different technical specifications for starter batteries. The most common forms are car and truck starter batteries. The Battery Council International (BCI) defines numerous groups of standard battery sizes. The relevant standard for motor vehicle batteries in Europe is the European standard (EN) 50342 (“ Lead-Acid Starter Batteries ”). The EN-50342-2 (“ Dimensions and Marking of 12 V Batteries ”) standard defines the external dimensions of car batteries and the EN-50342-4 (“ Dimensions of Batteries for Heavy Vehicles ”) standard for trucks.

The maximum dimensions for car batteries are (H × W × L) 190 mm × 175 mm × 393 mm and 240 mm × 273 mm × 518 mm for trucks. Six cells in series with the poles on the long side are common for cars and two rows of three cells with the poles on the short side for trucks. Since the weight depends on the amount of lead used, the weights of car and truck batteries differ greatly: they are between 10 kg to 30 kg for cars and 35 kg to 65 kg for trucks.

nominal voltage

The actual voltage of the on-board network of motor vehicles is above the nominal voltage of the starter battery while driving, since this should be charged while driving. The end-of- charge voltage is temperature-dependent. With 12-volt batteries, it should be 14.4 V (for reason and context, see above). Nevertheless, the nominal voltage of the starter battery is usually specified as the voltage of the vehicle electrical system. For passenger cars, 12 V is usually used, for trucks 24 V, for older cars (especially built before 1970) and for some motorcycles, 6 V is also common.

Nominal capacity

The capacity Q is given in the unit of measurement ampere hours (Ah) for here z. B. 20 hours discharge time T at 27 ° C (K20). A fully charged starter battery with a specified nominal capacity Q = 36 Ah can then deliver an average current of I = 1.8 A at 25 ° C for 20 hours . With the formula Q = I · t mean current - for a given capacity and in due course following the - at slightly decreasing voltage also decreases I = Q / T : Here, then,

If an electrical load is clamped to the accumulator, the maximum possible time results with:


U call : Nominal voltage at the terminals
P rated : connected nominal power (load)
Q is : capacity
T : time

With higher amperages, lower temperatures or advanced aging of the starter battery, the actual capacity is lower than the nominal capacity. The cause are non-linear relationships between charge and discharge current strength, which is referred to as the Peukert effect and can be roughly determined using the Peukert equation .

During a discharge with a constant current strength, the speed at which the voltage of the starter battery falls changes. The mean value of the voltage during the discharge time, which would allow the calculation of the energy or work in the unit of measurement watt-hour (Wh), is not given.

Examples of the capacity of starter batteries
Scooter 50 cm³ 4 to 12 Ah (12/6 V)
Motorcycle: 4 to 18 Ah (12/6 V)
Small car 36 Ah (12 V)
Car (compact class) 28 to 50 Ah (12 V)
Car (middle class) 40 to 70 Ah (12 V)
Car (luxury class) 55 to 120 Ah (12 V) and more (12 V, 24 V)
Truck (up to 7.5 t) 175 Ah and more (12 V, 24 V)
Truck (from 7.5 t) up to 225 Ah (2 X 12V battery)

The required capacity is based on several criteria:

  • Displacement (starter torque ): Single-cylinder engines with the same overall displacement require a higher battery capacity than multi-cylinder engines, since the starter has to deliver a higher torque for a compression stroke . The torque of a starter, like that of an engine, is determined by the displacement.
  • Type of fuel: Diesel engines with the same displacement require a larger battery due to the higher compression pressure.
  • Electrical consumption while driving: Strong electrical consumers influence the required capacity, since the starter battery serves as a buffer at low generator speeds and high consumption (possibly negative charge balance). Some vehicle manufacturers therefore deliver vehicles with high electrical loads (e.g. air conditioning) with a more powerful starter battery as standard.
  • Electrical consumption when the vehicle is stationary: Furthermore, electrical consumers that are also active when the vehicle is stationary (anti-theft alarm system, keyless entry, etc.) will reduce the so-called downtime of a vehicle until the engine is just started successfully (e.g. on a motorcycle after the Winter) shortened. The capacity loss of the battery when the car is not used is around 15-20 Ah per month. Here, too, some manufacturers deliver their vehicles with more powerful batteries depending on the electrical consumers.

Take-back law for starter batteries in Germany

According to the German Battery Act (BattG), which came into force on December 1, 2009 ("Act on the placing on the market, return and environmentally compatible disposal of batteries and accumulators"), there is a deposit obligation for vehicle batteries in Germany according to Section 10:

  • "(1) Distributors who hand over vehicle batteries to end users are obliged to charge a deposit of EUR 7.50 including sales tax per vehicle battery if the end user does not return an old vehicle battery at the time of purchasing a new vehicle battery. The distributor who collected the deposit is obliged to reimburse the deposit when returning an old vehicle battery. The distributor can issue a token when collecting the deposit and make the refund dependent on the return of the token. If the old vehicle battery is not returned to the distributor collecting the deposit, the person authorized to collect the old vehicle battery in accordance with Section 11 (3) is obliged to confirm the return in writing or electronically at the request of the end user without refunding the deposit. In deviation from sentence 2, a distributor who offers vehicle batteries using remote communication is obliged to reimburse the deposit even if a written or electronic return certificate is presented in accordance with sentence 4, which is not older than two weeks at the time of submission. "
  • "(2) If vehicle batteries installed in vehicles are given or passed on to the end user, there is no deposit obligation."

Section 6 of the Battery Ordinance (BattV) applied here until December 1, 2009 .

Take-back regulation for used vehicle batteries in Austria

According to § 12 of the Battery Ordinance, which came into force on December 26, 2008 (Ordinance of the Federal Minister for Agriculture, Forestry, Environment and Water Management on waste prevention, collection and treatment of used batteries and accumulators), end consumers in Austria can return used vehicle batteries at least free of charge . Return options are the final distributor of vehicle batteries, collection and recycling systems set up by the manufacturer or collection points of the municipalities (municipal associations). In the context of the mail order business, the final distributor is obliged to set up at least two publicly accessible offices per political district and to inform the final consumer of the opening times in a suitable manner.


According to the Basel Convention , a used starter battery is considered hazardous waste . The recycling of such old batteries in developing countries, where the lead is recovered by hand, is a health and environmental hazard .


  • Jürgen Kasedorf, Richard Koch: Service primer for vehicle electrics . Vogel Buchverlag, Würzburg 2001, ISBN 3-8023-1881-1
  • Rudolf Hüppen, Dieter Korp: Car electrics all types . Motorbuchverlag, Stuttgart 1972, ISBN 3-87943-059-4
  • Adolf Senner: Electrical engineering . 4th edition, 1965, Verlag Europa-Lehrmittel
  • Norbert Adolph: Car electronics / basics and building proposals . Schulfernsehen publishing company, Cologne 1979, ISBN 3-8025-1128-X
  • Bosch: Technical briefing on batteries . Robert Bosch GmbH, Stuttgart 1974, VDT-UBE 410/1 (technical brochure)
  • Konrad Reif: Batteries, electrical systems and networking. Vieweg + Teubner Verlag, Wiesbaden 2010, ISBN 978-3-8348-1310-7

Web links

Wiktionary: Car battery  - explanations of meanings, word origins, synonyms, translations

Individual evidence

  1. Johnson Controls Power Solutions Europe : Recommended charging for AGM batteries. In: , March 21, 2011
  2. Bridge like the pros. In: November 20, 2002, accessed May 4, 2015 .
  3. Quote from the vehicle's charging system. In:
  4. The magic eye of the battery. In: Retrieved January 19, 2015 .
  5. ^ RIS: Entire legal provision for the Battery Ordinance - Federal law consolidated. In: , version of October 27, 2014
  6. A1160 - Waste lead-acid batteries, whole or crushed ( Memento from October 10, 2005 in the Internet Archive )
  7. Top Ten Environmental Sins: What Burdens the World. In: , October 22, 2008