Battery Options

Background

Lead Acid

Ryobi 48V mowers came with four 12V lead acid batteries wired in series to create a 48V battery bank. The voltages here are considered nominal voltage and are not the actual voltage. The actual voltage of each battery is closer to 13.15V when it's fully charged and 52.6V for the battery bank, but it will vary depending on the batteries, their condition, and temperature. Lead acid chemistry produces 2V per cell. Again these are nominal values and the actual voltage is a little higher. Each 12V battery has six 2V cells. To produce 48V, we need 24 cells or 4 12V batteries.

LiFePO4

LiFePO4 (read this as lithium iron or lithium iron phosphate) cells are 3.2V nominal. To get a similar voltage to a 48V lead acid battery, 16 cells are wired in series for 51.2V nominal. You will sometimes see this listed as 16S LiFePO4. While the fully charged voltage ends up being a little higher than lead acid, it's still within the acceptable range and this provides two benefits. The first is that the charging voltage is almost the same as the lead acid. The second is, through most of the discharge, all the way down to 20%, the LiFePO4 will provide voltage equivalent to a fully-charged lead acid battery.

While this is all interesting, the main thing you need to know is you may see LiFePO4 batteries listed as 48V or 51.2V, sometime both for the same battery. The 48V refers to the lead-acid equivalent nominal voltage and the 51.2V refers to the LiFePO4 nominal voltage. Just make sure the battery is has 16 cells or a rated voltage of 51.2V.

What about 4 x 12V LiFePO4?

You may have seen 12V LiFePO4 batteries. These each have 4 cells in series, so putting 4 in series will get you the 16 cells you need. Since the stock batteries are 4 x 12V, you might think this is a good option. Let's look at the pros and cons.
Pros:

• If you get batteries close to the size of the stock batteries, you can mount them in the exact same way.

Cons:

• The batteries can become imbalanced, causing charging or operating issues

• Batteries often aren't rated for as high of a current load

• More connections

• More components leading to higher chance of failure

• More difficult to remove the battery (If it gets colder than -4°F / -20°C where you store the mower, you'll want to store the battery inside) 

As you can see, the cons outweigh the pros, so I will only be listing 48V batteries here.

Notable Deals (January 13, 2025)

I'll try to keep this updated with current deals.

• DCHouse 48V 100Ah

  • $660 on Ebay with code FRESHTSTART (Jan 13 - Jan 24)

• Eco-Worthy 48V 50Ah

  • $391 on Ebay with code FRESHSTART (Jan 13 - Jan 24)

This is one of my favorite batteries! It fits very well in the Ryobi ZT480 and RM480 mowers, it's not very expensive, and has proven very reliable. These batteries are sold under both the DCHouse and Eco-Worthy brands. The batteries are the same except the stickers. The DCHouse commonly sells for $344 on Ebay with a coupon. The Eco-Worthy commonly sells for $368 on Ebay with a coupon.

You can buy this battery directly from DCHouse, from Ebay, or from Amazon. In all cases, it will ship from the same place. Most North American shipments come from a warehouse in California. There are regular sales on Ebay, usually requiring a coupon code. Less often, but usually a better deal, there are sales on DChouse's website. Amazon sometimes has coupons too.

DCHouse Links:

Note: The DCHouse battery currently has low stock in North America. Expect new stock in March 2025. Order Eco-worthy until then.

• DCHouse (No sales tax)

  • During sales, look for a coupon code next to the "Add to cart" button or use 5FROMYOURFRIEND for 5% off any time

• Ebay (Currently removed due to low inventory, will update link when available)

• Amazon (Currently removed due to low inventory, will update link when available)

Eco-Worthy Links:

• Ebay

• Amazon

When this battery came out  at the end of Summer 2024, it lowered the price point for 100Ah batteries and has shown to be just as reliable as it's 50Ah little brother. It commonly sells for $660 on Ebay with a coupon and occasionally $640 (no sales tax) with a coupon on DCHouse. 

You can buy this battery directly from DCHouse, from Ebay, or from Amazon. In all cases, it will ship from the same place. Most North American shipments come from a warehouse in California. There are regular sales on Ebay, usually requiring a coupon code. Less often, but usually a better deal, there are sales on DChouse's website. Amazon sometimes has coupons too.

Links:

• DCHouse (No sales tax)

  • During sales, look for a coupon code next to the "Add to cart" button or use 5FROMYOURFRIEND for 5% off any time

• Ebay

• Amazon

You can also get this battery with an 18A charger. It's usually  $100 more than buying that battery alone. While this is a good charger,  it doesn't come with a charge plug and is more intended as an on-board charger for use in golf carts. I wouldn't use it on-board on a mower because it can become caked in debris and overheat. To use it externally, you can add an EZGO RXV charge plug, but it might be easier to buy a different charger that  already comes with one.

With 18A charger:

• Ebay

• Amazon

This battery was the go to 100Ah option for conversions until the DCHouse 100AH battery came out. In fact, the price of the Chins battery has fallen noticeably since then. They have very similar specs, but the Chins tends to be a little more expensive. While you may find them on Ebay or AliExpress, Amazon tends to have the best prices. Be sure to check for coupons. Expect to pay something in the low $700's. Sometimes buying it bundled with a charger is a better deal, but, like the DCHouse, these chargers are not specific to these batteries and don't come with a charge plug.

Battery Only

Battery with 10A Charger

Battery with 18A Charger and Battery Monitor

If you're looking to save a few bucks, there seems to be multiple accounts on Ebay that sell used Chins batteries, likely returns. You can find one here.

RM300e Options

The RM300e differs from the other RM480 and ZT480 in that the battery tray does not slide out the back and the mower is smaller overall. Some space can be gained by cutting the angle iron the surrounded the bottom of the stock batteries. Many have reported this allowed use of the DCHouse and Chins 100Ah batteries listed above, but the fit was still tight. Below are listed smaller options that other have reported success with.