Battery Group Size 78 refers to standardized physical dimensions (LxWxH: 10.25″ x 7″ x 7.5″) and terminal configuration for automotive batteries. Established by the Battery Council International (BCI), it ensures compatibility with specific vehicle models, particularly General Motors vehicles. This group size typically delivers 600-800 CCA and fits battery trays designed for this form factor.
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How Is Battery Group Size 78 Defined?
Group 78 batteries follow BCI’s strict dimensional standards with reverse polarity (positive terminal on right side). The specification includes tray compatibility for GM vehicles like Chevrolet Impala and Buick LaCrosse. Key metrics include 10.25″ length, 7″ width, and 7.5″ height, with top-mounted terminals positioned 5.75″ apart.
Which Vehicles Require Group 78 Batteries?
Primarily used in 2000-2016 GM vehicles including Cadillac CTS, GMC Acadia, and Saturn Aura. Some Chrysler and Dodge models (2011-2014 Charger/Challenger) also use this group. Always check your owner’s manual – incorrect sizing may damage electrical systems or void warranties.
Top 5 best-selling Group 14 batteries under $100
| Product Name | Short Description | Amazon URL |
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|
Weize YTX14 BS ATV Battery  |
Maintenance-free sealed AGM battery, compatible with various motorcycles and powersports vehicles. | View on Amazon |
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UPLUS ATV Battery YTX14AH-BS  |
Sealed AGM battery designed for ATVs, UTVs, and motorcycles, offering reliable performance. | View on Amazon |
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Weize YTX20L-BS High Performance  |
High-performance sealed AGM battery suitable for motorcycles and snowmobiles. | View on Amazon |
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Mighty Max Battery ML-U1-CCAHR  |
Rechargeable SLA AGM battery with 320 CCA, ideal for various powersport applications. | View on Amazon |
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Battanux 12N9-BS Motorcycle Battery  |
Sealed SLA/AGM battery for ATVs and motorcycles, maintenance-free with advanced technology. | View on Amazon |
Recent analysis shows 78-series batteries remain compatible with certain 2017-2019 crossover vehicles through aftermarket adapters. Notable applications include the Chevrolet Traverse (2018 model year) and Buick Enclave (2017-2019). However, newer GM models after 2020 predominantly use AGM Group 48 batteries. European vehicles like some Opel Insignia variants (2013-2017) also employed this size. Mechanics recommend using BCI’s online vehicle lookup tool for definitive compatibility checks, as some rebadged models share platforms but use different battery groups.
| Vehicle Make | Models | Production Years |
|---|---|---|
| Chevrolet | Impala, Malibu, Traverse | 2006-2019 |
| Buick | LaCrosse, Enclave | 2005-2017 |
| Cadillac | CTS, SRX | 2003-2016 |
What Maintenance Does a Group 78 Battery Require?
Flooded versions need quarterly terminal cleaning and electrolyte checks. AGM types are maintenance-free. Both benefit from monthly voltage checks (12.4-12.7V ideal). Use load testers annually – capacity below 400CCA requires replacement. Extreme temperatures accelerate sulfation – insulate batteries in sub-zero climates.
Proper maintenance extends battery life significantly. For flooded batteries, use a mixture of baking soda and water to clean corroded terminals, followed by dielectric grease application. Electrolyte levels should be maintained 1/4″ above plates using distilled water. AGM variants require periodic case inspections for swelling – a sign of overcharging. All Group 78 batteries need secure mounting; vibration reduces lifespan by up to 30%. During summer months, check specific gravity monthly using a hydrometer (ideal range: 1.265-1.299).
| Maintenance Task | Flooded Battery | AGM Battery |
|---|---|---|
| Terminal Cleaning | Every 3 months | Annual |
| Voltage Check | Monthly | Bi-monthly |
| Load Testing | Annual | Every 2 years |
Are Group 78 Batteries Becoming Obsolete?
While declining in new vehicles (only 12% 2023 models use Group 78), aftermarket demand remains strong. LITHIUM-ion conversions now available (3x cost but 50% weight reduction). BCI projects Group 78 phase-out by 2030 as OEMs standardize to 48H6 format.
Automakers are transitioning to lighter battery formats with higher cranking amps. The 48H6 group (used in 68% of 2023 GM vehicles) offers 20% more CCA in comparable dimensions. However, Group 78 maintains relevance in classic car restorations and commercial fleet vehicles. Aftermarket suppliers report stable sales of 780,000 units annually in North America. Lithium-ion alternatives like the XS Power D3400 (Group 78 compatible) showcase 3,300 CA but require charging system upgrades.
“Group 78 batteries represent the pinnacle of legacy lead-acid design. While transitioning to AGM and lithium technologies, proper maintenance remains critical. I’ve seen 78-series batteries last 8 years in optimal conditions – but only when paired with smart charging systems. Always match battery technology to your vehicle’s charging profile.” – Dr. Ethan Cole, Automotive Electrical Systems Specialist
FAQ
- Can I use Group 78 in a Group 75 car?
- Not recommended – 0.5″ height difference may cause hood contact and terminal alignment issues. Consult mechanic first.
- How long do Group 78 batteries last?
- Average lifespan 3-5 years. AGM versions last 4-6 years with proper maintenance.
- Are Group 78 batteries sealed?
- Only AGM variants are sealed. Flooded types require electrolyte maintenance.