U1 vs U1R Battery: Head to Head Comparison


The U1 and U1R type batteries of the BCI (Battery Council International) group are generally used for lawnmowers, electric scooters, golf carts, garden tractors, electric wheelchairs, and similar kinds of mobile vehicles. The battery helps the engine to start and enables the machine to perform more efficiently.


If you want to upgrade or maintain your machine’s performance, replacing the old battery will be a good start. However, you must know the differences between U1 and U1R batteries before you jump for your purchase.

Here, we are going to provide you with a complete guide – U1 vs U1R battery – where you will find dimensions, features, comparisons, recommendations regarding the batteries. Stick to the end if you don’t want to miss out on the additional information!

What does U1 mean on a battery?

The group U1 batteries are advanced gel-cell-based and sealed/non-spillable. This type is popular for medical and security purposes, such as wheelchairs, lawnmowers, electric carts, etc. The construction and material of the U1 battery are capable to deliver more power and more consistent performance than most of the other types.


The U1 batteries provide extended durability than the lead-acid batteries because of their gel-based construction. Most of the U1 batteries are made for general purpose use. However, a few are designed as starting-only. High-performance or starting U1 batteries feature 300-320 CCA Amps. On the other hand, the general-purpose U1 batteries provide at least 300-350 Amps.

Additionally, there are lithium-ion U1 batteries available in the market. This type offers higher capacity, a larger number of charging cycles, less weight. However, this type may cost you a fortune.

U1 vs U1R batteries: Similarities

The U1 and U1R batteries of the BCI group are mostly gel-cell-based, non-spillable, vibration-resistant, and Absorbent Glass Mat (AGM) batteries. AGM enhances the battery’s performance over standard lead-acid batteries.

Both types feature 35 Ah 20h capacity on average. The BCI group batteries feature 12V with a standard size of 7.72” (L) x 5.14” (W) x 6.14” (H).

U1 vs U1R batteries: Key Difference

To simply put, the U1 and U1R batteries are just two branches of the same tree; the only difference between the types is the position of the terminals. With the battery label facing you, the U1 batteries have the positive terminal on the left side. On the contrary, you will find the positive terminals on the right side in U1R batteries. Hence, the addition of the letter “R” with U1 implies the location of the terminal of a U1R battery.

When choosing a battery for your mower, keep the type in mind. You may find the mower’s battery cables too short to connect to the battery if the terminals are in the wrong locations. Therefore, the location of the terminal between U1 and U1R batteries plays a significant role.

U1 vs U1R Battery: Comparison at a Glance


Category U1 Battery U1R Battery
Standard Size 7.72” (L) x 5.14” (W) x 6.14” (H) 7.72” (L) x 5.14” (W) x 6.14” (H)
Position of the terminals Left Positive Right Positive
Voltage 12V 12V
Average CCA 200-250/300-320 depending on the model 200-250/300-320 depending on the model


Lawn Mower Battery: U1 vs U1R

CCA refers to the Cold Cranking Amps of a battery. It is the power available to turn over an engine in cold condition. During the winter, the engine oil gets thicker in a cold environment, hence it gets difficult to start the engine. Therefore, you should always go for the highest CCA for your lawnmower battery. Additionally, a battery with an Amp-hour rating of at least 100 tends to perform efficiently for riding lawnmowers.

The U1 type battery has an average CCA of 300-320. You will also find exceptional ones with a 350 CCA in the market. If you have a gas-powered lawnmower, you may prioritize CCA over the deep cycle of your battery. However, the Amp-hour should be the determining element if you are getting the battery for your battery-powered lawnmower, lawn tractor, garden tractor, etc.

Now, here’s our suggestion for lawn mower battery/lawn tractor battery: you may go for the Mighty Max U1 battery if you need a U1 type for your mower. It features 320 CCA, excellent deep cycle capabilities with AGM technology. 

If you are looking for a U1R type, the Deka U1R AGM battery may serve you the purpose with a CCA rating of 320 Amps.

Key Difference: U1L vs U1R Battery

The group U1 lawn mower batteries are available in two types – U1L and U1R. The key difference between the two types is the reversed position of the terminals. While facing the battery label, a U1L battery features the positive terminal near the left corner, on top of the battery. On the other hand, a U1R battery has its positive terminal on the right side.

Key Difference: U1R vs U1P Battery

The location of the positive terminal is on the right side of a U1R battery.  On the contrary, the U1P type features a top post terminal for easy hook-up and installation.

Frequently Asked Questions:

Here is a little additional information you might be looking for!

  • How long does a U1 battery last?

Answer: Most of the batteries have a definite life cycle and it’s around 5 years or so. However, a battery with a higher CCA may provide you with extended durability. Because, lawnmowers or tractors may require a fixed voltage, CCA differs from engine to engine.

  • What does U1R mean on a battery?

Answer: The U1R on a battery means the location of the positive terminal is on the right side of the battery. Here, the letter “R” with U1 implies the right side of the terminal.

  • What is the best U1L battery?

Answer: The Mighty Max Battery ML-U1 is the best U1L battery for its efficient performance in high and low temperatures. The 12-volt battery comes with 200 CCA (Cold Cranking Amps) and dimensions of 7.75” x 5.11” x 6.25”. The spill-proof battery comes with a 1-year warranty.



If you get the U1 and U1R batteries from the same manufacturer, they are most likely to be identical in size, amp hour, CCA, etc. You can use one as the other’s replacement battery. Therefore, you can interchange the batteries depending on the location of your machine’s battery.


Here’s the take on the U1 vs U1R battery – the difference in the location of the positive terminal. Therefore, before making your purchase, don’t forget to check the battery cable of your machine.

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