Battery groups › 78
BCI battery group
Group 78 battery size
A BCI group 78 battery is at most 260 mm long, 180 mm wide and 186 mm tall (10.24 × 7.09 × 7.32 in), according to the Battery Council International group chart.
| Maximum size | 260 × 180 × 186 mm |
|---|---|
| In inches | 10.24 × 7.09 × 7.32 |
| Terminal types | S |
| Polarity | Standard layout for this group |
| Cold cranking amps (OE range) | 465–875 A |
Cars whose manuals point to group 78
None of the owner's manuals this site has read so far print group 78. Most Japanese and Korean makers print a case size or capacity instead of a BCI group, so the battery label on the car is the better guide.
Measuring for a group 78
To take a group 78, the tray needs at least 260 mm (10.24 in) of length and 180 mm (7.09 in) of width inside the hold-down, and 186 mm (7.32 in) of height below the hood or any bracket, with room left for the cable ends. These are BCI maximums: a real group 78 battery can be a few millimetres smaller, never larger. Original-equipment batteries in this group were rated from 465 to 875 cold cranking amps, so the right rating depends on the car; match or exceed the rating on the battery you are replacing.
Nearby sizes
| Group | L × W × H (mm) | Difference from 78 |
|---|---|---|
| 100 | 260 × 179 × 188 | 0 mm length, -1 mm width, +2 mm height |
| 58 | 255 × 183 × 177 | -5 mm length, +3 mm width, -9 mm height |
| 58R | 255 × 183 × 177 | -5 mm length, +3 mm width, -9 mm height |
| 97R | 252 × 175 × 190 | -8 mm length, -5 mm width, +4 mm height |
| 101 | 260 × 179 × 170 | 0 mm length, -1 mm width, -16 mm height |
Positive numbers mean the other group is bigger than group 78. A bigger case only fits if your tray and hold-down have that much spare room; measure inside the hold-down frame, not the old battery.
Fitting a group 78
The group sets the case size, terminal position and hold-down. A battery from another group can only replace it when the length, width and height all fit the tray and the terminals land on the same sides. No other passenger-car group in the BCI chart has exactly the same case size and polarity. Use the tray fit checker to list every group that fits a measured space.
Source: Battery Council International, BCI Group Sizes (Oct 2023 PDF), page 7. Checked 2026-10-20.