A marine starter battery is best but I have used deep cycle/starter 27 type for years on my 75hp ETEC i now use a size 24 starter (smaller) battery ..
Lithium phosphate are much smaller but just as powerful but there is lots of debate about OB charging circuits being incompatible with LiPo4 … AGM work and don’t leak !
a size 24 marine starter is likely best but read chatgpt opinion.
chat answer…
For a 1995 30 hp Evinrude outboard with electric start, you’ll want a marine starting battery rated for strong cranking power (measured in cold cranking amps — CCA) and a group size that fits your boat’s battery tray.
🔋 Typical Recommendation for a 30 hp Outboard
While the official 1995 Evinrude manual doesn’t list an exact battery size, practical and aftermarket sources show that BCI Group 24 is commonly used and works well for a 30 hp Evinrude with electric start. One boater specifically mentioned using a Group 24 battery with ~550 CCA without issues.
General marine guides also suggest that 30–50 hp outboards typically need batteries with good CCA — often around 500–700+ CCA — with Group 24 being a common fit for space and performance.
⚠️ Important: If you have lots of electronics (fishfinder, lights, etc.) that run off the same battery, consider a larger battery (e.g., Group 27 or Group 31) or a dual-battery setup so starting power isn’t reduced by accessory loads.
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