How to Replace Lead Acid Battery with Lithium Ion

The lithium-ion technology, as it is referred to, is a popular choice because of the benefits it has specifically over the lead-acid technology. But when you want to replace one for the other, you need to keep an eye on some operating conditions. This is for safety as well as to get the most out of your newly installed lithium-ion batteries. We’ll go over that in this post.

Unscrew the batteries from the vehicle. Remove the connections between the batteries and take each lead-acid battery out one at a time. Put them in a dry place till you can safely get rid of them. Place the lead-acid batteries in the vehicle’s metal casing. Connect the positive of the connectors wires to the positive terminals of the battery and do the same with the negatives. Tighten the screws and switch on the vehicle. Check the battery status on the LCD and see if the motor is spinning.

Whether it is your RV or boat, at some point you will realize that your lead-acid batteries are just not holding charge. You could recondition them with the help of desulfators and prolong their life, but if you have done that a few times, you know it is time to let them go.

Instead of replacing them with a new set of lead-acid batteries, it is time to consider switching to lithium-ion batteries, the newer renewable energy storage option. And when you do, here is how you do that.

Can I Replace Lead Acid Battery with Lithium Ion?

Replacing lead acid batteries with lithium ion is possible. But there is a way to do it and you must keep some precautions in mind. But before we jump into the process, you need to know a few terms that are often thrown in this context.

Things to Know Before the Replacement

Drop-in Replacement: This is a popular term. When used in the context of replacing batteries, it means that you don’t have to change any equipment like inverters after switching the lead-acid ones for the Li-ion ones. You just need to change the already programmed settings in the charge controller of the inverter.

Charge Controller: Speaking of which, if you are using shore power or an alternator or solar power to charge your lead-acid batteries, you might not need to change the charge controller after all.

You just need chargers with an adjustable charge rate to keep the voltage and charging profiles for Li-ion batteries in order. And when you are looking into these chargers, make sure you check the configuration recommended by the battery manufacturer.

Typically, a 14-volt absorb rate which takes just about two minutes which is a lot less than that of the lead-acid batteries. If the float voltage is less than 14 volts you can avoid overcharging too. Usually, it is 12 volts because that is the voltage window for lithium.

It is important to remember that lithium batteries don’t need to be charged to 100 percent. In fact, it is better to keep them partially charged at, say, 90 percent especially if you are going to leave the vehicle in storage for the season.

Alternator: Lithium batteries do not have as much internal resistance as lead-acid batteries. This means they can accept charge from the alternator according to their needs. But the alternator can end up damaging itself because those machines are not meant to be running at full speed for a long period of time.

You can prevent this by using a DC/DC convertor or replacing the alternator with one that is meant for higher amperage charging. Those also have temperature control features which is a bonus. If you use a DC/DC converter, you can limit the amount of current drawn by the battery. Ideally, keep it at half the battery’s rating.

Cranking Amps: The cold crank amps for lead-acid batteries show the amps used when you start an engine in really cold weather. Li-ion batteries don’t have these. So when you are replacing them for a starting battery, you want to be sure that your new lithium-ion battery can handle the current flowing through it. So, be sure to check the rating. Make sure you have a backup in case this doesn’t work out the way you planned.

Battery Monitoring: This is the final precaution to note. All battery systems can monitor individual batteries and the entire pack of batteries which is often called the battery bank. Now, this is not just about volts. You must also keep an eye on the amps that are going in and out of the entire bank. Also check the temperature to get a full idea of the state of the bank. Some monitoring systems come with Wi-Fi or Bluetooth and the monitor on your phone will tell you exactly these details. You might want to look into that.

Step-by-Step Guide to the Replacement Process

  1. 1
    As is always the case, never neglect safety in these situations. So, get yourself a pair of safety gloves and goggles before you start the process of changing the batteries.
  2. 2Get a lithium-ion battery that matches the voltage of the controller and the motor of your vehicle. If you are doing this for a 60-volt scooter, the motor power should not be more than 2 kilowatts. And the controller peak amperage should be less than 35 amperes.
  3. 3
    Switch off the vehicle’s miniature circuit breaker which is a device that protects the circuit from any accidental surges. When you switch it off, you protect yourself from accidental electrical shocks.
  4. 4
    Using a screwdriver, remove the metal clamps around the lead-acid battery in the vehicle. Note that at this point the wires are still attached to the battery so if you don’t take it out carefully, you might see some sparks. That is why the safety gear is not optional.
  5. 5
    When there are multiple lead-acid batteries, you will notice that they have interconnected wires among them. Using a screwdriver, remove the screws and disconnect the wires. Keep these batteries in a safe and dry place till you figure out how to get rid of them safely.
  6. 6
    The batteries are typically placed in metal casings in the vehicle. Remove any debris and clean the cases properly.
  7. 7Get your new lithium-ion battery and place it in the clean metal case.
  8. 8
    Connect the positive of the battery to the connector wire and do the same with the negative terminals. If it is not clearly marked on the battery, you can use a multimeter to determine the terminals.
  9. 9
    Tighten the screws with the screwdriver and shut the panel.
  10. 10
    Turn your vehicle on and check the battery status on the LCD screen. Then check if the motor is spinning. If yes, pat yourself on the back for a job well done.

Frequently Asked Questions

Which Is Better Lead Acid Battery or Lithium Battery?

Lithium-ion batteries are relatively eco-friendly and use about 20-30 percent less energy than lead-acid batteries. They don’t need as much maintenance as lead-acid batteries. Li-ion batteries can be charged indoors. The batteries are smaller in size and their operational range is higher than lead-acid batteries. Li-ion batteries increase the life cycle and have no memory effect. They are also lightweight compared to lead-acid batteries.

Can You Use a Lithium Battery Charger on a Lead Acid Battery?

You can but ideally, you shouldn’t because all chargers are different. If you want to do this, you must see if the charger has something called an equalization mode. Set the charger to no more than 14.6 volts and disconnect it after the battery is charged. Otherwise, they damage the batteries.

About the author, Phil Borges
