Can You Mix Old and New Golf Cart Batteries? 

If you have an electric golf cart, then you understand how much of a handful they can be and you may be tempted to save some money and mix old and new golf cart batteries. Rather than having one large golf cart battery, most electric golf carts have a bank of four to eight batteries. Therefore, one or two of the batteries can give out while the others are working fine. When this happens, people often wonder if they can mix old and new golf cart batteries or if they have to replace the entire bank. 

It’s possible to mix old and new golf cart batteries if one or more of the batteries in your bank gives out, but just because you can mix old and new golf cart batteries doesn’t mean you should. Mixing can lead to safety issues and reduced performance of the golf cart and the remaining batteries.  

While mixing old and new golf cart batteries to save money is tempting, this usually isn’t a good idea, and this article will explain why. We’ll also discuss the better alternative to mixing old and new batteries and some of the consequences of combining them. 

Is It Bad to Mix Old and New Golf Cart Batteries? 

In the strictest sense, it’s definitely possible to mix old and new golf cart batteries. As long as the batteries are the same brand and size and are compatible with your golf cart, they should work fine. However, you should only temporarily mix old and new golf cart batteries if you’re stranded somewhere. Once you’re in a safe place and have the opportunity to do so, you should replace all your batteries with new ones. 

What Can Happen When You Mix Old and New Batteries? 

Corroded Golf Cart Battery
Mixing Golf Cart Batteries can lead to overcharging causing corrosion

While possible, mixing old and new golf cart batteries isn’t recommended. There are a number of things that can happen when you do this. Most of these problems stem from the differences in amperage and power of the batteries. 

A Discrepancy in Electrical Capacity 

The most significant risk of mixing old and new golf cart batteries is the electrical discrepancy that will ensure. The newer batteries will have more electrical capacity than the old ones in the cart, which means they’ll have more power. Contrary to what you may think, the various strengths of the batteries won’t offset and even out. Instead, the discrepancy will worsen the longer you use the batteries together. 

Poor Cart Performance 

Because not all the batteries will provide the same amount of power and electricity, it will affect the carts’ performance. You’ll find that the cart doesn’t have as much power when going up hills and that the batteries die faster than they used to. The combination of less power and weaker batteries will lead to poor cart performance. 


Overheating is one of the dangerous by-products of having new batteries supplying more power than old ones. The new batteries will push their power through the older ones with less capacity and resistance. As a result, the increased power may prove too much for the old battery to handle, and it will overheat. 

When a battery overheats, it can melt the terminals, power cables, or components near the battery. This can cause irreparable damage to these components, and you’ll have to replace them. 

Battery Leaks and Safety Hazards

As the batteries overheat, it could cause their casing to break down and disintegrate, resulting in leaks. Lead acid batteries can leak either water or battery acid, and both will cause issues. Battery leaks are also dangerous because they could potentially lead to an explosion if it leaks onto the wrong part of the golf cart. You should replace leaking golf cart batteries immediately, whether they’re old or new. 

Can You Replace a Single Golf Cart Battery if the Others are Good? 

Because of the dangers involved with mixing old and new golf cart batteries, it’s best to replace all of them rather than a single one. The exception to this rule is if the expiration dates of the batteries are very close to one another. You can also replace a single battery rather than all of them temporarily, but not for long-term use. 

Finally, if the rest of the batteries in your battery bank are less than one to two years old, you may not have to replace all the batteries at once. Use a multimeter to measure the amount of voltage of each battery, and if they’re the same as the new one you’re about to install, there’s no need to replace them all. 

When to Replace a Golf Cart Battery

Obviously, if a battery isn’t working properly, it’s important to replace it. However, there are other instances when replacing a golf cart battery is necessary. And depending on how old the rest of your batteries are, you may have to replace the entire bank. 

  • If it has physical, visible damage such as bulging or cracking. 
  • If one or more of the batteries is leaking. 
  • Your golf cart isn’t operating as smoothly or with as much power as usual. 
  • You notice your lights or radio isn’t working in your golf cart. 

Our Favorite lead acid replacement is from Trojan. Here is their 8v model that works great in many carts. If you have a golf cart that uses 12 volt batteries, these are great.

Frequently Asked Questions 

Do you have to replace all golf cart batteries at the same time?

If your batteries are less than one year old, you may not have to replace all of your batteries at once. However, if your battery bank is more than two years old and one of the batteries needs to get replaced, it’s best to replace all the batteries at once. 

Here is an in depth article about replacing just one battery at a time.

Can you mix and match carts and batteries?

Because different battery brands use different formulas and varying chemistries than others, it’s never a good idea to mix and match carts and batteries with different brands. 

How many years should golf cart batteries last?

Golf cart batteries should last anywhere from four to ten years, depending on how often the cart gets used and how well the batteries get maintained.