Battery Equivalents and Replacements

Group 26 And Group 26R - Dimensions and Features

BCI Group 26 and BCI Group 26R batteries are mid-range starting batteries used very often in cars, SUVs, smaller trucks, power generators, smaller boats, etc.

BCI Group 26 and 26R batteries feature practically the same dimensions, electric features, and terminal types, with the only difference being terminal orientation.

megavolt 26 and 26r w650px

 BCI Group 26 and Group 26R Batteries Size and Specifications

BCI Group 26 and Group 26R batteries feature nominal dimensions of (L x W x H) 8 3/16 x 6 13/17 x 7 3/4 inches (8.1875 x 6.8125 x 7.75 inches, 208 x 173 x 197 mm), with most lead-acid group 26/26R batteries weighing 28-30 pounds (12.7-13.6 kg).

Practically the only difference between these two batteries is the terminal orientation:

- BCI Group 26: positive terminal to the left, negative to the right,

- BCI Group 26R: positive terminal to the RIGHT (hence the 26R), negative to the left.

The following comparison chart lists some of the most popular BCI Group 26 and Group 26R batteries with their most important features and specifications:

Model Battery Type Cell Type Capacity CCA MCA RC Weight (lbs/kg)
AntiGravity AG-26-24-RS Starting LiFePO4 24 Ah 1000 - - -
Centennial 26R-75 Starting Flooded - 500 625 75 28 lbs; 12.7 kg
DieHard 26R Starting Flooded - 575 720 81 28.41 lbs; 12.9 kg
Duracell 26R Starting ? - 540 665 80 -
Duralast 26R-DL Starting Flooded - 575 715 90 28.41 lbs; 12.9 kg
EverStart VP-26R Starting Flooded - 540 - - 38 lbs; 17.2 kg
Exide E26R-EX Starting Flooded 51 Ah 500 600 80 29.4 lbs; 13.3 kg
Exide S26R-EX Starting Flooded - 550 660 85 29.4 lbs; 13.3 kg
Generac 5819 Starting Flooded - 525 - - 30 lbs; 13.6 kg
Interstate M-26 Starting Flooded - 500 625 85 -
Interstate MT-26 Starting Flooded - 525 655 85 -
Megavolt 26-60-500 Starting Flooded 50 Ah 500 620 - 28 lbs; 12.7 kg
Megavolt 26R-60-500 Starting Flooded 50 Ah 500 620 - 28 lbs; 12.7 kg

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As one can see, most of the BCI Group 26 and Group 26R batteries are lead-acid flooded/wet batteries, with nominal (20h) capacity of ~50Ah, 500-575 Amps CCA rating, 600-720 Amps MCA rating, and RC value of 75-90 minutes.

Note: although modern starting lead-acid batteries tolerate deep discharges better than the older lead-acid batteries, these batteries are optimized for cranking/starting applications - deep discharges should be avoided.

However, lithium group 26/26R batteries are slowly entering the market - AntiGravity AG-26-24-RS features a nominal capacity of 24Ah, but it is able to provide 1000 Amps, ensuring safe starting of surprisingly large diesel and petrol engines.

Also, it allows the users to save some weight, which can be important for performance vehicles.

antigravity ag 26 24 rs

Another very important feature of the AntiGravity AG-26-24-RS battery is its Re-Start feature - if the battery is discharged below a certain level, the builtin Battery Management System will disconnect the battery from the car's electric system with enough charge remaining for one (or a few) more engine start attempt.

How to Charge Group 26/26R Batteries?

When the group 26/26R batteries are connected to the vehicle's electric system, let the electric system charge the battery.

However, if the battery is charged outside of the vehicle, then:

- lead-acid group 26/26R batteries should be recharged using advanced lead-acid battery chargers with a charging current of up to 6-8 Amps (or as recommended by the battery manufacturer) - just be sure to set the charging mode (wet/flooded lead-acid battery) properly.

- lithium group 26/26R batteries should be recharged using lithium battery chargers in the 10-20 Amps range (or as recommended by the battery manufacturer) or an advanced lead-acid battery charger with the dedicated lithium battery charging mode.

Note: Most lead-acid wet/flooded group 26/26R batteries are NOT maintenance-free and they are NOT spill-proof batteries - they must be kept in upside position and periodically the user has to check the electrolyte level.


everstart 26r w250px

Long Story Short: BCI Group 26/26R batteries feature physical dimensions of 8.1875 x 6.8125 x 7.75 inches (208 x 173 x 197 mm), however, not all group 26/26R batteries are built to the standard - some models are usually longer and still labeled as group 26/26R batteries.

Thus, before getting a new group 26/26R battery, be sure to check the actual dimensions of the old group 26/26R battery, its battery compartment, and of course, the terminal orientation.

Amazon Search:

- Group 26 Battery

- Group 26R Battery

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