
Dangerous but valuable – a battery for a vehicle always has a limited lifespan. Modern materials are extending this voltage more and more. Generally, two to three new batteries can be expected in the course of a car’s life. Since vehicle batteries contain hazardous substances such as lead or sulfuric acid, they must be disposed of professionally. Legislation has established a deposit system for this purpose, which is intended to support environmentally friendly replacement. Here we inform you about how to dispose of an old car battery.
motorcycles, cars and trucks with internal combustion engines have so-called "lead batteries". These are used to store the current produced by the alternator while driving and to supply the starter motor when the car is started. They also serve as a voltage buffer, so that the correct voltage always reaches the respective consumers, even when the alternator is running at different speeds. After all, it supplies the on-board electronics of a car even when the engine is not running: lights, indicators, radio, interior lighting are kept in operation by the battery for several hours, even when the engine is off.
Structure of the battery
A battery or. Lead acid battery in a vehicle consists of:
- A plastic casing
- Multiple chambers
- Lead plates
- Acid
- If necessary. Screw caps
- Two poles

The acid-resistant plastic housing usually reliably holds the acid inside the battery for its entire service life. Only in case of accidents it can crack or break. Otherwise, the manufacturers are now very reliable in this respect.
The chambers indicate how high the voltage is that a battery can offer. The following always applies: two volts of voltage are provided per chamber. A moped battery with three chambers has correspondingly 6 volts, a car battery with 6 chambers has always a 12 volts voltage and truck batteries are usually equipped with 12 chambers, which can deliver correspondingly 24 volts. However, the 12 volt voltage is only a theoretical and somewhat outdated value. Today, the normal nominal voltage of a battery is always 14.4 volts.
The electric current enters the battery through the so-called "electrolysis process". Current flows from the alternator through the poles into the lead plates and the acid. The acid is charged with free electrons that can be retrieved at any time. To prevent the battery from "overcharging", the alternator is equipped with a regulator that stops charging when the battery’s nominal voltage is reached.
Possible damage
Batteries can suffer damage from four causes in addition to violence:
- Aging
- Deep discharge
- Short circuit
- Drying out
The permanent charging and discharging process forms so-called "lead crystals" inside the battery. These sit loosely on the lead plates and over time can sink down into the bottom of the battery. When the layer of lead crystals has grown to the point where it reaches the plates, the cell is short-circuited. The battery is then usually unusable.
Deep discharge occurs when the battery is not charged for several months. This can happen quickly, especially with vehicles in storage. A cold outside temperature further promotes deep discharge. But do not be deceived: a battery is already considered damaged and deep discharged when the nominal voltage is lower than 11.8 volt has fallen!

Another cause of deep discharge is when consumers are operated with the engine stopped until the battery is too discharged. In the past, this was often the case with the vehicle lighting. Today, a deeply discharged battery is no longer necessarily irrecoverably lost. For some years now, the industry has been offering chargers that can be used to repair deep-discharged batteries. Repairability is still within a narrow range here, but it is worth trying in any case. All well-stocked car repair shops, especially those of the well-known chains, offer this service for little money.
A short-circuit between the poles is very unusual in itself, but can easily happen when handling tools with the hood open. If, for example, a wrench accidentally falls between the poles, a short circuit can occur. Usually the battery acknowledges this with a bang and the key flies away. However, the battery may have been damaged beyond repair. If the short circuit remains switched for too long, there is a risk of fire and explosion! For this reason, the positive terminal of the battery must always be covered.
A battery always needs a certain level of dissolved acid. With older and sometimes still very cheap batteries today, the acid level must still be checked regularly. However, most new batteries today are maintenance-free. If the acid level needs to be topped up, use only distilled water. After filling and charging, the battery is usually repaired if it dries out.
Replacing a car battery
Replacing a battery is actually quite simple. The accumulators are firmly screwed in place with a holding device. First, however, the screw connections on the poles are loosened. Then loosen the lock until the battery can be removed. All batteries today have a retractable handle, which makes removal much easier. When lifting out the battery, be careful not to touch it with your clothes. It is always very likely that the battery has sweated out some acid. This is not dangerous for the body, but after the next wash, holes may be eaten into the clothing.
Ideally, the battery should be placed in a sturdy transport box with a handle. If such a box is not available, a plastic bag can make the transport much safer. It is placed in the trunk and secured with straps to prevent it from falling over.
Before installing the new battery, a few things should be checked. These are
- bottom plate of the battery holder
- Ground cable
The bottom plate of the battery holder can be very rusty. It is strongly recommended that this rust is first resealed by sanding, priming and spray painting, otherwise the sheet metal will sooner or later crumble away altogether.
The ground cable is the black cable that connects to the bodywork. It is completely removed. Then clean both ends of the cable down to the bare metal with a wire brush and sandpaper. Proceed in the same way with the contact point on the body. Thread and contact plate are ground down to the sheet metal before the ground cable is refitted. After screwing on the ground cable, the area is sealed with battery polish. By doing this, you have effectively prevented a so-called "ground fault". In the worst case, this can be harmful to the vehicle’s electronics. most of the time these faults manifest themselves by annoying errors: brake light and turn signal change when flashing, strange noises occur or the radio cannot be operated.

Now insert the new battery. First, screw the battery to the locking device. Only then set the connections to the poles. Technically you should not be able to mix them up. The plus pole is red and marked with a +, the minus pole is black and marked with a -. Accordingly, the red cable is connected to the positive terminal and the black ground cable to the negative terminal.
It is now extremely important that you reassemble the intended cover of the poles. This is supplied with the battery and affects at least the red positive terminal. If you are caught at a general vehicle inspection with a missing cover on the plus pole, this will cost you a 90 euro fine and two points in the central traffic register. If, in addition, the battery is not properly screwed down, the penalty is even more expensive.

Disposing of old batteries
The old battery is not household waste or bulky waste, but must be disposed of professionally. You can do this yourself by taking the battery to a recycling center drive. You will receive at least a receipt, but usually also a few euros for the recyclables. a battery contains several kilograms of lead, which can be reused just like any other metal, without any problems and as often as desired.

You can also go to any point of sale where car batteries are purchased. As a rule, you will have bought a new battery before removing the old one. On the receipt you will receive the item "battery deposit" to the amount of 7.50 euros should be noticed. After replacing the old battery, simply return it with the receipt to the place where you bought the new battery and you will get your 7.50 euros back. When buying a new battery, you can also submit the receipt from the recycling center. They are not charged for the deposit.
Legal framework for battery take-back
recycling centers and sales outlets for new batteries are obligated to take back used batteries. the appropriate legislation is called "battery law" and states in its paragraph 10 that the sellers who sell vehicle batteries to the end-users are obliged to collect the deposit of 7.50 euro, which they return when taking back the old battery.
Legally, however, sales outlets can only accept batteries that they sell themselves. If a supermarket sells car batteries, for example, it is not legally obliged to accept either motorcycle or truck batteries. Mostly, however, the sales outlets are accommodating in this point.
The acceptance of batteries at sales outlets must, however, be in "normal household quantities. Hobby used car dealers should therefore always have purchased at least the corresponding quantity of new batteries from the same store before handing in the old batteries. If this is agreed with the store beforehand, there is no harm in doing so. With appropriate, friendly communication, you can always avoid a lot of trouble. Recycling centers, however, accept batteries in any quantity. However, from a certain size, it can also become chargeable, because for private individuals, the requirement of the household quantity also applies at the public collection points. Here, too, the recycling center should be informed prior to the delivery of a large item. Roughly speaking, we recommend this measure from the delivery of 10 old batteries.
The disposal of the old batteries should also be carried out quite quickly. Used batteries are special waste that may not be stored on private property.