Can You Use a Car Battery for an Electric Bike?

Electric bikes, or e-bikes, are becoming an increasingly popular mode of transportation in cities throughout the United States. It is mainly because they offer several advantages over traditional gasoline-powered bicycles and cars.

Perhaps the most significant advantage is that they’re much cheaper to operate than cars. They also produce zero emissions, which is excellent for the environment. Additionally, they’re much easier to park than cars and can often navigate through traffic more efficiently. Finally, e-bikes are a lot of fun to ride.

One of the questions most frequently asked about e-bikes is whether or not you can use a car battery on an electric bike. After all, most people who would consider purchasing an e-bike probably already own a vehicle.

If you can use the battery from your car to power your e-bike, that would save you the time and money it would take to purchase another battery for your bike.

Unfortunately, it’s not as simple as removing the old battery from your electric car and replacing it with one meant for an electric bicycle.

First, though, let’s look at the difference between car batteries and bike batteries.

Read How Much Does Insurance on an Electric Bike Cost?

Table of Contents

Difference Between Car and Bike Battery

Car batteries tend to be much larger than bike batteries and produce more power. Car batteries create 12 volts of direct current at around 600 cranking amps, perfect for starting your car.

On the other hand, bike batteries only produce about seven volts of DC and 150-200 cranking amps. This difference in voltage and power makes it difficult to switch out a car battery with a bike battery without making some modifications to the electric bicycle itself.

Another difference is the material used in each battery. Car batteries are filled with lead plates, spaced apart by sponge-like substances. It creates an environment where the reaction inside the battery can occur easily, giving off a lot of power quickly.

Bike batteries are not made up of lead plates but instead have several smaller cells that contain the electrolytes necessary to produce energy.

Read What is the best folding electric bike on the market?

Can You Use a Car Battery on an Electric Bike?

While it’s technically possible to use car batteries on an electric bike, there are several drawbacks that you’ll want to consider first.

Sulfuric Acid

One of the most significant dangers is that if you get into an accident while riding your e-bike, any wires surrounding your battery could contact with sulfuric acid found in car batteries. It could result in severe burns and injuries, mainly because the acid would be very close to your skin, where it can easily penetrate and cause damage.

Another problem is that you might inadvertently overload the system by hooking up a battery made for a much more robust vehicle than yours.

It’s also challenging to recharge a car battery once it’s been drained of power (which tends to happen quickly when used on an e-bike). You’ll need either a special charger or alternator built specifically for recharging car batteries.

One final problem with car batteries and e-bikes is that the lead wires can be hazardous if you’re involved in an accident. If they were to contact sulfuric acid, it would affect your health.

Read What to Look For When Buying Electric Bike

Space Issues

Another vital drawback to using a car battery on an electric bicycle is that it simply doesn’t fit. Electric bikes typically use more compact batteries than cars, and replacing your old battery with something meant for a different size vehicle will require that you re-adjust the seat and handlebars to accommodate the new design of the e-bike.

A car battery is also much heavier, which will make it even more difficult for you to handle the bike, even if you could find a place to put it. In addition, you’ll also have to purchase a charger for your car battery, which means even more money.

Read How Far Can You Go On an Electric Bike?

Time of Usage

Car batteries are also typically only good for about two years, at which time you’ll need to replace them anyway. On the other hand, electric bike batteries can last up to five years if well-maintained and charged correctly, so there’s little point in using a car battery on an electric bicycle.

Question of Volts

In addition to the safety concerns and problems, it’s challenging to obtain a car battery for an e-bike. There is also the question of volts.

As mentioned previously, most batteries made for cars produce around twelve volts of DC power that must be converted into AC by your electric bicycle’s motor before it can be used.

It means you’ll have to invest in some expensive equipment if you want to use your car battery on your bike regularly. In the end, it’s not worth it to use a car battery on an electric bicycle.

While these are just some of the most significant reasons why you can’t use a car battery on an electric bike, it should be clear that this is only something you’d want to do if all other alternatives failed.

Read Can You Use An Electric Bike Without A Battery?

Best Ways to Power Your Electric Bike

Fortunately, there are plenty of other options available for powering your e-bike if you’re interested in clean transportation.

Electric Outlet

If you want another option that won’t cost you anything upfront or require any special tools or equipment, consider using a standard electric outlet in your home to charge your bike when not in use.

It’s easy enough to plug it into an empty socket attached to the wall behind the couch while you’re enjoying some downtime, and you don’t need any special equipment to do it. You can also use extension cords with an electric outlet for more flexibility in choosing your bike to be located while it is charging.

Solar Charging

Another option for power to lessen the amount of money you’ll ever spend on electricity is using solar panels to directly charge the battery on your electric bicycle.

It will make it possible for you to leave your e-bike outside during the day so that it can soak up some sun rays and become charged, instead of having to pay a utility company each time you need to charge up your bike later at night.

The advantage here is not only that this option requires little effort or money on your part, but also that there are no health risks involved, which means you’ll be able to hook your bike up to an adapted car battery as well if you like.

Read Can You Ride an Electric Bike on Beach?

Electric Bike Batteries

Of course, there are plenty of batteries you can buy that already have the appropriate output for your bike so that you don’t have to worry about any complicated rewiring.

These are often slightly more expensive than one-size-fits-all batteries explicitly designed for e-bikes, but this may be an option worth considering if cost is a concern.

A new battery will likely come with its charger, and you’ll be able to get started charging up and riding without having to do anything else.

You’ll also find that most bike shops offer the service of changing out your old battery for a new one when necessary, which means you can avoid doing it yourself whenever possible.

Pedal Power

Lastly, you can use an electronic bike without a battery. While this won’t be useful for electric bikes that are meant to go fast, it is helpful for those who want to pedal slowly around town without being plugged in.

For many e-bikes, there is also an option of turning the throttle on the handlebar entirely off so that you can use it as a traditional bicycle. It means you’ll never have to worry about recharging the battery at all if you don’t want to and still get plenty of exercise like usual.

Also, read Can I Get Help to Buy an Electric Bike?

Conclusion

In short, you cannot use a car battery for an electric bike. While there are some options to consider if you’re looking into clean transportation, such as hooking your bicycle up to an electrical outlet or changing out the battery yourself, car batteries produce far too high of a voltage. In addition, they can easily be fatal if mishandled.

It’s also challenging to find equipment that will allow you to hook up a car battery to your e-bike without spending even more money than it would cost to buy a new battery and charger instead and not have these issues.

Suppose you want the most significant possible power source for your e-bike. In that case, electrical outlets attached directly to walls at home may be an excellent option for those living in city apartments with no yard to hook up a solar panel outside.

If you have the money, buying a new battery from the store will also save you the time and effort required to change your old one or find compatible hardware if you want to use an adapted car battery instead.

And finally, learning how to work on a bicycle without a battery can make it possible for you to reduce how much money you spend on transportation altogether while still incorporating some exercise into your daily routine.