What are battery terminals?

Battery terminals are the electrical contacts used to connect your car to your battery. These terminals can come in a wide variety of shapes and sizes.  

Car batteries typically have one of 5 types of terminals:  

-SAE Post – two lead posts (shaped like a cone with the top cut off) on top of the battery 

-JIS Post – two lead posts but smaller than the SAE post.   

The positive terminal will always be larger than the negative terminal on both the SAE and JIS type post. 

-Side Post Battery terminals – two recessed threads into which bolts, or battery terminal adapters are to be attached. These sockets are the same size for both negative and positive. 

-L Terminals – as per the name, L shaped posts with a hole through the vertical side.  Typically used on European Cars, Motorcycles and Lawn mowers. 

Stud – these are threaded stud. Sometimes the positive and negative are different diameter sizes but usually they’re the same. 

Marine batteries typically have 4 posts, a pair of threaded posts for both the positive and negative terminals and a pair of SAE posts (as above) . 

There are 4 main types of battery configurations: 

  1. positive on left and negative on the right corner on the long side of the battery 
  2. negative on the left and positive on the right corner on the long side of the battery 
  3. positive on left and negative on the right corner on the short side of the battery 
  4. Negative on left and positive on the right corner on the short of the battery 

Does it matter which side the positive terminal is on?  

Yes it matters. Purchasing the wrong configuration may prevent battery cables from reaching the battery terminals. If your cables can’t reach your battery – well, then, the battery can’t go.  

How can I tell which is the positive and negative terminal on my car battery?  

Car battery terminals will typically be marked and colour coded.

 A plus sign ‘+’ and red colour for positive and a negative sign ‘–‘  and black colour for negative.  

On occasion the colour will be absent or it’s just too dirty to tell, so it’s always important to not just rely on the colour and to look for the negative or positive sign stamped into the battery near the terminals. 

How do I tell the width of my terminals?  

See our photo of how to measure your battery terminal below: 

Why do I need to know the difference between the positive and negative terminals on my car battery? 

Well if you ever find yourself stranded with a dead car battery you’re going to hope you strike a kindly passer-by who can give you a jump start but failing that you’ll be wanting to use your own jump starter (power pack or jumper leads) , in which case it’s going to be important to know the difference between your positive and negative terminals. 

Still confused about battery terminals?  

No problem.  We’re here to help, contact us at the Battery Warehouse, our staff are here to supply any technical advice or after-sales service you may need. 

Want the peace of mind of knowing you can jump start your car on your own?  Then you can find a car jump starter here