How to Increase Car Battery Voltage

How to increase car battery voltage is simple. It’s one of the do it yourself exercises that can save you several dollars.

We all believe once a car battery loses its ability to retain power, it’s time to replace it. Thankfully, this article will change your mindset.

A car battery is a vital component. But it can mess up your daily plan if it fails to start your car engine.

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It’s draining to jumpstart the car every morning before leaving for work. Or, just in the middle of your journey, you beg other motorists for help.

How a Car Battery Voltage Drops
car battery

How a Car Battery Voltage Drops

Although manufacturers assure us car batteries require less maintenance, they are subject to many risks. Take a look;

  • Extreme heat

Regardless of being manufactured to operate around the engine’s high temperatures, a car battery is subject to high temperatures.

High temperatures evaporate water from the battery cells and cause it to produce low voltage.

  • Cold temperature

Cold temperatures slow down chemical reactions inside the battery. Car batteries are believed to lose around 35% of their strength during cold seasons.

  • Unused for an extended period

Car batteries lose power with time if they stay unused. It’s known as self-discharge. The batteries lose around 1% of their charge daily through self-discharge.

  • Unclean terminals

Corroded terminals cause discharge. Additionally, dust and grime increase the discharge rate too.

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How to Increase Car Battery Voltage
Battery terminals

How to Increase Car Battery Voltage

A car battery left in a discharged state for a long time can run low. At this state, a typical car battery charger won’t recognize it.

To boost charge your already dead or low car battery, you’d want to use parallel charging. Parallel charging entails using a similar fully charged battery to equalize the low battery’s voltage.

I will walk you through how to increase battery voltage output.

There are two simple phases in the procedure. Let’s dive in;

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Jumper Cables, Battery, Engine, Car
Car battery terminals


Step 1: Find a fully charged sealed lead battery of 12 volts, similar to the low battery.

Step 2: Cable the two batteries in parallel. Use high-quality jumper cables to perform the exercise.

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Attach one end of the red clip to the positive terminal of the fully charged battery and the other end to the positive terminal of the low battery.

For the black clips, attach each end to the negative terminals of each battery.

Step 3: Leave the batteries for around 3 days for the low battery to equalize. Place them in a cool and well-ventilated area with proper covering.

Step 4: After 3 days, use a digital multimeter to confirm the low battery has attained 12 volts.

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Set the multimeter to direct current (DC). Place the red probe on the positive terminal and the black probe on the negative terminal. Then, read on display to confirm it’s around 12 volts.

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In the second phase, I recommend Noco genius smart car battery charger to restore your battery. The smart charger has an inbuilt microprocessor that minors the battery condition.

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Step 1: Connect the battery to the charger.

The battery will automatically detect and engage pulse charging mode. It sends out high electrical currents for a short duration.

The pulse mode removes sulphur build-up from the lead plates.

Step 2: Observe until the charger defaults back to regular charging.

At this stage, the charger will have fully desulphated the battery. Leave it overnight to charge fully. Note that the charger will automatically shift to storage mode once the battery is full.

The storage mode maintains optimum charge to ensure the battery cells remain safe.

Step 3: Check if the charger indicates 100% charged.

Install the battery in the car and test. You’re ready for the ride.

How Do I Prolong the Life of a Car Battery?

A car battery can cause you much agony if it fails to start the engine. Ensure your battery is fully charged to avoid troubles every time you need to leave for daily activities.

Take a look;

  • Ensure it’s always fully charged

Regularly test your car battery using a digital multimeter to ensure it’s 12 volts. A fully charged battery has a longer lifespan than a low-charged battery.

Other than the engine alternator charging it, recharge it with the appropriate charger every 3 months.

  • Regularly check the electrolyte level

The average electrolyte level should cover the lead battery plates in all six cells. If you can see the plates, refill using distilled water.

  • Keep the top clean

Keep the lead-acid battery’s top clean. To retain the charge, the terminals should be free of corrosion, dust, and grime. Regularly clean the battery top and apply a battery terminal protector.

  • Tightly fasten the battery

Tightly fasten your battery in the car to avoid excessive vibrations. Excessive vibrations cause short-circuiting of the inner components.

  • Minimize driving for short trips

Driving for short trips will not produce enough power to recharge the battery fully. The starter motor uses much of the battery charge when you start the car engine.

  • Avoid exposing the battery to low or high temperatures

Low temperature drains the car battery. On the other hand, high temperatures evaporate the water from the cells.

Properly insulate your car battery to regulate the temperatures.

  • Minimize power usage when the engine is off

Avoid leaving the headlights on or listening to music for an extended period when the engine is off.

  • Regularly use your car

Car batteries have a discharge rate of around 1% daily. Regularly driving your car will maintain the battery by fully recharging it. 

FAQs on Car Battery Voltage

Is 11.6 Volts Enough to Start a Car?

If the battery voltage is lower than 11.8 volts, it will be hard to start the engine. You can try switching off other electrical appliances before starting the engine.

How Do I Know When My Car Battery Needs Replacing?

– When your vehicle struggles to start even after recharging.

– The battery hasn’t been in use for a more extended period.

– The battery triggers the dash light.

Before making a final decision to dispose of your car battery, try to revive it. The two phases on how to increase car battery voltage can save you from buying a new battery. 

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