How to tell if you have a “Bad” battery?

///How to tell if you have a “Bad” battery?

How to tell if you have a “Bad” battery?

We get the phone calls all the time. “My batteries are bad”. Here at Lifeline we understand that the battery or batteries appear to be all bad. The reality is this is very unusual and sometime impossible. We hope to clarify a few things that can assist you in determining what might be the cause of the failure.

The first thing to keep in mind is that the batteries will take the brunt of any failure. If your charger fails, the symptoms show up in the battery. If you leave a load on, the symptoms will show up in the battery. If your solar controller or any other charging source fails, the symptoms will show up in the battery. This is important to know when determined what happened to the battery. The simple solution of course is to replace the batteries. We hear it all the time. We put in new batteries and everything works! Of course it does because you have new batteries. The question remains, how did they fail?

A battery can also fail. The most common defect is a dead cell. If your battery has a dead cell it will not register any higher than 10.5 volts. A dead cell means that the connection between one of the cells on the inside has been broken. With Lifeline batteries a dead cell is very uncommon but not impossible.

The best place to start is to determine the cause of the failure. You can look through the list below of common failures and see if any of these match your symptoms.

  1. All of my batteries in my bank are dead!
  2. We hear this a lot. If your entire battery bank fails, it was most likely caused by something else. Maybe the charger was not charging properly or it wasn’t turned on. Maybe shore power was disconnected. Maybe you left the vehicle or vessel and something was left on. Having an entire bank fail suddenly is like all 4 tires on your car going flat at the same time. The best way to solve this is to check the voltage on the batteries and then find an auxiliary charger to help boost them up to a voltage that your on board system will recognize.

Q. My battery bank will not charge above 12.2 volts or my run time between charges is not what it used to be. 

A. This is the #1 sign that your batteries are sulfated. Batteries get sulfated from sitting for long periods with no charge on them, accidentally getting drained down without a recharge and the biggest cause is not fully recharging your batteries after each use. Please refer to the blog post about equalizing batteries.

Q. I disconnected all my batteries and one is 2 volts lower than the others. 

A. This very well could be a battery with a dead cell. It is a misconception that if one battery goes bad it will ruin all the other batteries. The reality is they can appear that way when they are all hooked up together in a bank. Once they are broken down and the bad one is removed you could hook the others back up and they would work just fine to keep you going.

Q. My batteries have a charged voltage over 13.0 volts but there is no power when the load is applied.

A. This is a common sign of overcharging. The AGM (Absorbed Glass Mat) has been dried out due to too much voltage from the charger. You need to check your chargers output voltage to make sure it falls within our guidelines.

Please feel free to contact our technical support team at any time for questions about warranty and product information.