What Happens if You Put Two Batteries in Parallel?

After the famous Super73 battery upgrade, dirt bikers have started to look into creative ways they can modify their bikes. Having an additional battery is a very popular option.

However, what happens if you put two batteries in parallel? And what’s the right way to install an extra battery on your bike? Keep reading, because we’ve answered these questions below. 

What Happens if You Put Two Batteries in Parallel?

When you connect two batteries in parallel, you increase the total current flowing through the circuit while still keeping the voltage the same. This means if you install two batteries in parallel in your electric dirt bike, you provide it with a current boost, which can increase speed. 

Secondly, putting two batteries together parallel increases the capacity of the circuit. This means two batteries will hold more charge than one, and so the bike’s range will increase. You’ll be able to go farther after only charging the bike once. 

Additionally, if the voltage remains the same, the resistance doesn’t change either. So you’d get more current with a smaller resistance, which is simply perfect. Resistance causes energy loss. The less energy you lose, the less your system heats up, and the more power you get. You can simply say goodbye to overheating. 

What happens if you put two batteries in parallel? Your bike can go faster and longer than ever before. 

Will Two Batteries in Parallel Last Longer?

Yes, two batteries in parallel last longer. If you attach two 12V batteries, and they have a 50A rating, the circuit will have 100A of current. This means you’ll have more current available to keep your bike running, and it’ll last longer. At the same time, the voltage would remain the same. 

However, the only way a setup like this would work is if the batteries had the same voltage and current rating. If one battery has a higher voltage rating, it will have a higher current and will overpower the other. Instead of the batteries working together, they will compete with each other. 

Do Batteries in Parallel Drain Equally?

Yes, batteries in parallel drain equally. Once you connect the batteries, their current is merged, and both batteries provide equal current at all times. However, if one battery had a higher voltage rating than the other, you’d be in a tough spot.

 One battery would discharge before the other because they are not the same. This would still increase your range because the batteries would provide a greater current, however, you wouldn’t get it all at once. Also, the resistance would divide too. The battery with the higher voltage rating would overheat extremely fast, which is never a good thing.

The first battery would die very fast, and then only the other would be left. You wouldn’t get the combined, increased current, which would defeat the whole purpose of the upgrade. What happens if you put two batteries in parallel? Unless the batteries are similar, nothing useful. 

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Arsal Sher — Mud Bike Writer

With an interest in dirt bikes developing from an early age, Arsal now pursues his passion for bikes by restoring old ones. He specializes in vintage collectibles and works hands-on with motorbikes when he has time to spare from his content writing career.


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