What battery is the right one for my vehicle?

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Where Can I Get My Battery Checked?

According to the 2024 ADAC breakdown statistics, 44.9% of all vehicle breakdowns are caused by battery issues (see: https://www.adac.de/rund-ums-fahrzeug/unfall-schaden-panne/adac-pannenstatistik/ ). Ensure your battery isn’t one of them. Find a trusted VARTA ® Partner near you and get your vehicle battery checked! Go to VARTA Partner Finder

How can I prolong my vehicle's battery life?

To extend your vehicle's battery life, consider these tips: Charge Care: Regularly monitor and charge the battery, especially during long-term parking or winter storage. Charge every two months if used sporadically. Check Charge: Regularly check battery charge, particularly in cold weather or after short trips. Dimming headlights indicate low charge. Prioritize Safety: Conserve battery by minimizing non-essential electrical use and keeping safety systems active during long drives. Clean Installation: Keep the battery and terminals clean to prevent discharge and enhance charging efficiency. For more information find our article "Correct battery care" Read Article

How can I prevent battery failure before winter?

Have your battery tested by a workshop before temperatures drop, especially if the vehicle is older or used mainly for short trips. Preventive testing is the most effective way to avoid battery problems in winter .

What to do when the car battery dies in winter?

Start by switching off all electrical consumers and trying a jump start with proper cables or a booster pack. If you repeatedly find the battery dead in your car , it’s often a sign of internal ageing rather than a one-off discharge. In that case, have the battery professionally tested to confirm whether it needs replacing and to prevent the issue from returning in winter.

Why do car batteries and cold weather cause so many problems?

Cold weather slows down the chemical reactions inside the battery, reducing its available power. At the same time, the engine needs more energy to start and heated features (lights, blowers, seat heaters) increase consumption. This combination makes battery failure and other battery problems in winter much more likely.

Why is my battery dead in winter?

Finding the battery dead in your car during winter is often the result of summer heat weakening the battery, with cold weather then reducing its remaining power. As temperatures drop, starting becomes harder and existing weakness becomes visible.

Battery Technology
Workshop Knowledge

Voltage stabilization during battery exchange

When a battery replacement is carried out, a voltage drop can cause problems. Maintaining the voltage is the solution.

When the engine is switched off, power is still drawn from the battery during vehicle diagnostics. In the case of a longer diagnosis, the battery installed in the vehicle can be discharged by the control units and other electrical loads to such an extent that the on-board system voltage falls below the permissible under-voltage limit of the control units and a corresponding entry is made in the fault memory and data is lost in the volatile memory section (e.g. steering angle sensor or end positions of the electric window lifters).

A constant voltage of the vehicle electrical system is therefore a prerequisite for professional troubleshooting or battery replacement and to avoid additional difficulties from the outset due to any undervoltage.

What is voltage stabilization?

Voltage stabilization describes the process of connecting an external power supply in order to maintain the voltage in the vehicle at a constant level when the battery is disconnected. This prevents the control units in the vehicle from registering a critical undervoltage and recording this as a fault in the event record.

“Mercedes sometimes reacts sensitively to this if you simply disconnect the battery and connect a new one: We already had a head up display that no longer works and problems with driver assistance systems. You have to use a diagnostic tool for that anyway. It could also affect the start/stop behaviour for a longer period of time.”
R. Nickel – CLARIOS Vehicle Application Engineer

Recommendation for voltage stabilization

The external power supply shall be connected before starting battery replacement or extended vehicle diagnostics.

NOTE: Never use a car battery charger to maintain voltage. Modern chargers use a special charging algorithm with different phases of charging. Sudden disconnection of the battery can lead to malfunctions in the charger, which can damage the vehicle electronics or charger.

When changing the battery, do not disconnect the installed battery until the external power supply has been connected and switched on.

The external voltage source must always be connected at points that are capable of safely carrying the required currents. For this reason, we always recommend connecting the external voltage source to the battery connection terminals for diagnostic purposes.

In the event of a battery change, the connection to the battery terminals is naturally somewhat more difficult to handle. Working on the cables can also cause the clamps of the external voltage source to drop or cause short circuits. If available, we recommend using the jump start connection points in the vehicle in this case. Information on where these are in the vehicle can be found in the VARTA Partner Portal.

NOTE: We advise against connecting the voltage maintenance via the OBD interface. According to the ISO 15031-3 specification, the maximum current carrying capacity of the connections is limited to 10A - a value that can quickly be exceeded if several control units wake up. This can lead either to serious and expensive damage to the OBD interface or to the fuse being blown, unnecessarily delaying diagnostic or repair work.

The easiest way certainly is to use a second battery as a secondary power source. With this approach, it is important to make sure that the system is protected against unintentional short circuits by a suitable fuse.

In everyday workshop use, stationary constant power supplies with sufficient power from 350W have proven their worth. In this power class, even the unintentional wake-up of one or more control devices does not immediately lead to a breakdown of the supply voltage.

Conclusion

Whenever a battery change or an extensive troubleshooting needs to be performed an additional voltage stabilization should be ensured. Always try to connect the external power source to the battery connection terminals. If this is difficult to handle we recommend using the jump start connection points. Beware of short circuits. Never use a voltage maintenance via OBD. Better go with a secondary battery or a constant voltage power supply of at least 350W instead.

You want to learn more about the different electrical systems in modern vehicles? Then our Advanced Automotive Training is definitely the right thing for you!

Find a trusted workshop

Do you want to rely on a car battery expert to service your vehicle? Go to our VARTA^® Partner Finder and locate a trusted workshop near you.

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Got a question?

Make use of our VARTA Battery Finder to find the battery product that fits your vehicle.
GO TO BATTERY FINDER
According to the 2024 ADAC breakdown statistics, 44.9% of all vehicle breakdowns are caused by battery issues (see: https://www.adac.de/rund-ums-fahrzeug/unfall-schaden-panne/adac-pannenstatistik/). Ensure your battery isn’t one of them.
Find a trusted VARTA^® Partner near you and get your vehicle battery checked!
Go to VARTA Partner Finder
To extend your vehicle's battery life, consider these tips:
1. Charge Care: Regularly monitor and charge the battery, especially during long-term parking or winter storage. Charge every two months if used sporadically.
2. Check Charge: Regularly check battery charge, particularly in cold weather or after short trips. Dimming headlights indicate low charge.
3. Prioritize Safety: Conserve battery by minimizing non-essential electrical use and keeping safety systems active during long drives.
4. Clean Installation: Keep the battery and terminals clean to prevent discharge and enhance charging efficiency.
For more information find our article "Correct battery care"

Read Article
Have your battery tested by a workshop before temperatures drop, especially if the vehicle is older or used mainly for short trips. Preventive testing is the most effective way to avoid battery problems in winter.
Start by switching off all electrical consumers and trying a jump start with proper cables or a booster pack. If you repeatedly find the battery dead in your car, it’s often a sign of internal ageing rather than a one-off discharge. In that case, have the battery professionally tested to confirm whether it needs replacing and to prevent the issue from returning in winter.
Cold weather slows down the chemical reactions inside the battery, reducing its available power. At the same time, the engine needs more energy to start and heated features (lights, blowers, seat heaters) increase consumption. This combination makes battery failure and other battery problems in winter much more likely.
Finding the battery dead in your car during winter is often the result of summer heat weakening the battery, with cold weather then reducing its remaining power. As temperatures drop, starting becomes harder and existing weakness becomes visible.