GC2 Battery: The 6V Golf-Cart Deep-Cycle Standard
GC2 is the battery that powers golf carts, and by extension a huge share of RV house banks and off-grid systems: a 6-volt, ~260 × 180 × 275 mm deep-cycle unit rated around 215 Ah (20h), wired in series strings of six (36V) or eight (48V). It has no cranking rating at all — it is built purely to be discharged and recharged, day after day.
Why 6 volts? The design logic of the GC2
A lead-acid cell is always about 2 volts, so a 6V battery is three cells and a 12V battery is six. In a case of similar footprint, the 3-cell battery gives each cell roughly twice the room of a 6-cell battery — room used for thicker, taller plates. Thicker plates are exactly what deep-cycle duty demands: they shed less material per discharge and survive hundreds of cycles that would kill a starting battery.
Since golf carts need 36V or 48V anyway, there is no penalty for using 6V blocks — six or eight of them in series is simply how the pack is built. The 6V format is a design choice, not a compromise.
GC2 at a glance
| Attribute | Typical GC2 value | Notes |
|---|---|---|
| Voltage | 6V (3 cells) | Wired in series for 12V / 36V / 48V systems |
| Dimensions | ~260 × 180 × 275 mm | Confirm height — taller than car batteries |
| Capacity | ~215 Ah (20h) | Also quoted at the 5h and 100h rates |
| CCA | Not rated | Deep-cycle construction — cranking is not its duty |
| Terminals | Flag / embedded | Bolt-down lugs; check pattern per maker |
| Chemistry | Flooded (maintenance / low-maintenance) or AGM | Flooded needs periodic watering |
Cross-verified typical ranges from the World Battery Hub data section and manufacturer datasheets; a specific battery's datasheet wins. Capacity figures always carry a discharge rate — the same battery prints a higher Ah at the 100h rate than at the 20h rate.
GC2 vs GC12: the 6V/12V decision
The BCI defines both a 6V GC2 and a 12V GC12 (about 327 × 181 × 278 mm, ~150 Ah). The comparison is the classic series-vs-single trade:
| GC2 (6V) | GC12 (12V) | |
|---|---|---|
| Capacity (typical) | ~215 Ah | ~150 Ah |
| To make 12V | Two in series → 12V, ~215 Ah | One unit → 12V, ~150 Ah |
| Plate design | Thicker (3 cells per case) | Thinner (6 cells per case) |
| Typical cycle life | Higher | Lower |
Two GC2s in series deliver more capacity and usually more cycles than one GC12 in a similar footprint — which is why the GC2 pair is the default RV and off-grid house bank. The series wiring itself is straightforward but must be done correctly; see series vs parallel wiring.
Maintenance: the flooded GC2's real cost
Most GC2s are flooded, and flooded deep-cycle batteries need periodic watering with distilled water, terminal cleaning and equalization charging — a real maintenance commitment that AGM builds avoid. The watering schedule and battery water level checks are part of owning a flooded bank, and neglect shortens life faster than cycling does. AGM GC2s trade that maintenance for a higher price, per the general AGM vs flooded comparison.
Where GC2 batteries are used
- Golf carts and utility vehicles — six in series (36V) or eight (48V).
- RV house banks — two in series for 12V; see the RV battery guide.
- Off-grid solar — series/parallel banks; see the solar battery guide.
- Floor scrubbers, lifts and sweepers — industrial motive power.
Key takeaways
- GC2 is a 6V deep-cycle standard — ~260 × 180 × 275 mm, ~215 Ah (20h), flag terminals, no CCA rating.
- The 6V design gives each cell room for thicker plates — the foundation of deep-cycle durability.
- Two GC2s in series beat one GC12: ~215 Ah vs ~150 Ah at 12V, typically with longer cycle life.
- Flooded GC2s need watering and maintenance; AGM versions trade maintenance for price.
What procurement buyers should check
- Is the capacity quoted with its discharge rate — and is it the 20h figure, not a flattering 100h figure?
- For bank purchases, are the units matched (same maker, lot, age) so the series string ages evenly?
- Is the duty cycling (daily discharge depth) within the maker's stated cycle-life curve?
- Flooded or AGM — has the maintenance budget (watering, equalization) been priced into the flooded option?
- Do the flag/embedded terminals match the fleet's cable lugs, and is the height verified against the battery box?
- Does the warranty cover cycle-life claims, and are those claims stated against a documented test standard?
Frequently asked questions
What is a GC2 battery?
A BCI-standardized 6-volt deep-cycle battery measuring about 260 × 180 × 275 mm with a typical capacity around 215 Ah (20-hour rate) and flag or embedded terminals. GC2s are wired in series — six for a 36V cart, eight for a 48V cart — and are also popular in RV house banks and off-grid systems.
Why are golf cart batteries 6 volts?
A 6V cell block allows thicker, taller plates per cell than a 12V case of similar footprint, which suits deep cycling. Carts need 36V or 48V anyway, so wiring six or eight 6V units in series costs nothing extra and gives a more robust, longer-cycling bank than fewer 12V batteries.
What is the difference between GC2 and GC12?
GC2 is 6V with roughly 215 Ah; GC12 is the 12V sibling with roughly 150 Ah. Two GC2s in series make a 12V, 215 Ah pair that outperforms a single GC12 in capacity and typically in cycle life — the reason GC2 pairs dominate RV and off-grid banks.
How long do GC2 batteries last?
In golf-cart duty a well-maintained flooded GC2 typically lasts around 4–6 years; in gentler RV or solar duty, longer. Depth of discharge, watering discipline and charge quality determine the number — cycle life claims should be tied to a stated discharge depth.
Sources
Cross-verified from the World Battery Hub entity database and public references; where sources differ, the difference is flagged rather than silently resolved.
- World Battery Hub data section — GC2 reference page and GC12 reference page.
- Battery Council International (BCI) — GC2 and GC12 group definitions and dimensional data.
- Manufacturer datasheets (flooded and AGM GC2, multiple makers) — capacity-at-rate, cycle-life and dimension cross-checks.
- Golf-cart OEM battery specifications — 36V / 48V pack configurations.
Last reviewed: 2026-09-22