The SLI24MDC Duracell Ultra Group 24M Battery appears to be a deep-cycle or dual-purpose marine/RV battery designed for starting, lighting, and ignition (SLI) applications. Group 24M typically indicates a mid-sized case (10.25″L x 6.8″W x 8.9″H) with top terminals, featuring spill-proof AGM or lead-acid chemistry. These batteries generally offer 70-85Ah capacity and 700+ CCA for reliable cranking power combined with cycling capabilities. Duracell’s Ultra line may include enhanced vibration resistance and extended cycle life compared to standard flooded batteries. Marine/RV models in this group size often balance reserve capacity (100-180 minutes) with deep discharge recovery for auxiliary power needs.
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What defines Group 24M battery dimensions?
Group 24M batteries follow standardized BCI sizing of approximately 10.25×6.8×8.9 inches (L×W×H). The “M” designation indicates modified terminal placement for marine/RV applications, typically combining top-post terminals with side terminals for accessory connections. This compact footprint allows installation in tight engine compartments while maintaining 70-90Ah capacity through advanced plate designs.
Marine Group 24 batteries prioritize vibration resistance with compressed AGM separators and reinforced grids. Unlike automotive counterparts, they’re built to handle both high-current cranking (600-800 CCA) and partial state-of-charge cycling. Pro Tip: Measure your battery tray clearance carefully—some AGM versions may be 0.2″ taller due to pressure relief systems. For example, Duracell’s Ultra SLI24MDC might use dual-purpose design allowing 400 cycles at 50% DoD while maintaining 750 CCA for engine starts.
How does SLI24MDC compare to standard automotive batteries?
Unlike conventional SLI batteries focused solely on cranking amps, the SLI24MDC employs dual-purpose technology blending starting power with deep-cycle endurance. While typical Group 24 car batteries offer 700-800 CCA but only 20-30Ah usable capacity, marine versions like this Duracell provide 600+ CCA alongside 50-60Ah accessible energy through thick paste plates and high-density active material.
Automotive batteries use thinner plates optimized for surface-area cranking, whereas marine/RV batteries incorporate ruggedized construction. The table below shows key differences:
| Feature | SLI24MDC | Auto Battery |
|---|---|---|
| Plate Thickness | 1.8-2.2mm | 1.2-1.5mm |
| Cycle Life @50% DoD | 400 cycles | 30 cycles |
Practically speaking, this means the SLI24MDC can power a trolling motor for 4-6 hours while still reliably starting engines—something regular car batteries can’t sustain. But what happens if you use automotive batteries for marine applications? You’ll likely experience plate shedding and premature failure within months.
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FAQs
Can SLI24MDC be mounted sideways?
Yes, AGM construction allows safe horizontal installation—unlike flooded batteries where electrolyte might leak. Ensure vent caps remain upright and avoid inverted mounting.
What’s the warranty period?
Typical marine AGM batteries carry 2-3 year free replacement warranties. Duracell Ultra models often include 18-24 month coverage with pro-rated extensions up to 48 months.
