Can I charge an RV deep cycle battery with a regular charger?

RVs come equipped with deep-cycle batteries that provide a steady output of power while you’re on the road. This means that your vehicle continues to gain power and equally lose charge over a period of time. So a deep cycle battery is a battery that is discharged regularly and needs to be recharged frequently.

Maybe that’s when you’re asking “can I charge my RV deep cycle battery with a regular charger?” The answer is yes, but it shouldn’t! A regular backup charger is never a good choice for an RV’s deep cycle battery. This type of charger is not very efficient and does not help extend battery life. There are many more reasons why you shouldn’t use a regular charger for your RV deep cycle battery. Let’s find out more here!

Do RV deep cycle batteries require a special charger?

Yes, RV deep cycle batteries require a special charger called a deep cycle battery charger, aka a smart automatic charger. These types of chargers are multi-stage chargers that can detect fast or bulk charging mode (when the battery is mostly depleted) and switch to trickle charging mode once the RV battery is full. With this stepped design, the charger can easily understand the battery status and apply voltage/current as needed. Even if you leave the charger on for several hours (not recommended), you won’t overcharge or damage your expensive battery.

When we use a regular battery charger to charge the RV battery. You don’t get a powerful short charge or high charge when you start your RV. Instead, it gets stable power output from deep-cycle batteries. Therefore, it works in a way that ordinary chargers cannot bring about the best results in terms of efficiency, maintenance, lifespan, etc. Let’s break down the main reasons here:

No voltage adjustment

Regular inverter chargers rely on constant voltage and do not adjust based on battery requirements. These chargers can also charge the battery at a higher rate while constantly applying higher voltage to the battery. And this is exactly the problem that deep cycle batteries cannot solve. As a result, your deep cycle battery may be permanently damaged by overcharging, resulting in high replacement costs!

low efficiency

Since regular chargers don’t have voltage regulation, they tend to generate too much heat while charging. But deep cycle batteries are not designed to handle this kind of overheating or rapid charging. As a result, your battery will not be fully charged, or it may display misleading information indicating that it is not actually fully charged! Therefore, what deep cycle RV batteries require is a stepped charging model where extremely depleted batteries are first charged at a high capacity and then charged at a tapering rate as the charge rate decreases. This results in fast and optimized charging times.

Unable to detect battery status

Ordinary backup chargers cannot detect the remaining voltage on the battery and therefore its overall status. This can lead to poor monitoring. Smart chargers, on the other hand, feature a convenient LCD display that monitors the condition of your deep-cycle battery, such as remaining charge time and current charge level.

lack of safety measures

Regular inverter chargers don’t come with as many safety features as smart RV battery chargers. Some of these features include overcharge protection, overheating protection, overload protection, and reverse polarity protection. Since your regular charger lacks these features, you could be putting your battery in great danger.

Lacks automatic functionality

Regular chargers also lack some automatic features. When the battery is full, your regular charger requires manual intervention to stop charging. But with a smart RV battery charger, charging stops automatically as soon as the battery is full. It can also notify you when your battery is degrading and can send you replacement notifications.

Can I use a 12 V charger to charge deep cycle batteries?

Let’s first understand what a deep cycle RV battery looks like. These are lead-acid batteries, usually with 6 cells connected in series. Charging deep cycle batteries in parallel can also keep the total voltage within 12V. Each cell typically produces about 2.1 V, and together they can produce up to 12.6 V, and during cycling, it can reach up to 14.6 V. Therefore, a 12 V charger with a built-in RV converter can produce the required output charge for a 12V RV deep cycle battery. ​

Smart chargers also use 12V output capacity, but their working principles are different from ordinary chargers. But what all 12V chargers follow is that they convert 120 V AC power into 12 V DC power and then direct it to the RV adapter. You can also get chargers with a 24V voltage output, but keep in mind that you cannot use a 24V deep cycle battery charger to charge a 12V RV battery or it will drain within minutes!

What is the best way to charge an RV deep cycle battery?

If you’ve found the right charger for your RV deep cycle battery and are looking for the best way to charge it, check out the following steps below.

  • Properly clean battery terminals using a mild solvent such as soda water and a wire brush
  • Make sure all cables are securely connected to the terminals
  • Connect the positive (red) cable to the positive terminal and the black (negative) cable to the negative terminal
  • Plug the charger into an AC or shore power outlet and turn it on
  • Monitor charging status in indicator light or display
  • Turn off the charger when you see the battery is full, for smart chargers the operation should stop automatically
  • Now unplug the charger and disconnect the cables in the reverse order of connecting them; black, then red
  • Apply some grease or petroleum gel to the terminals to prevent future corrosion

The batteries that MK can use for RV include lead-acid batteries (OPzV&OPzS Series, Pure GEL Series and AGM hybrid gel Series) and lithium iron phosphate batteries (Lead-acid Case LiFePO4 Battery). You can choose the one that best suits you according to your needs and actual applications. Battery. Feel free to contact us anytime!