The like-new batteries were purchased by customers who mistakenly bought the wrong capacity or incompatible batteries for their applications. We assure you that all like-new batteries are rigorously checked and tested to verify functionality and quality before delivery ( only a few have minor scratches on the surface). All like-new batteries qualify for the same 5-year warranty as our new batteries. Order with confidence knowing we stand behind the quality.【Grade A Automotive Cells & UL Certified 200A BMS】LiTime's 12V 300Ah LiFePO4 battery uses high-quality Automotive Grade LiFePO4 cells and a UL-certified 200A BMS for the utmost safety, higher energy density, greater power, and more stable performance. Trust our battery to keep you powered up and running smoothly with an excellent self-discharge rate and protection against overcharge, over-discharge, over-current, and short circuits.【Expandable for 40.96kW Capacity & 61.44kWh Energy】Upgrade your power supply with LiTime 12V 300Ah LiFePO4 Battery - 3840Wh energy and support for 2560W load power, perfect for solar homes, off-grid systems, RV campers, and emergency backup power. Connect up to 4 batteries in parallel & 4 in series for a massive 40.96kW capacity and 61.44kWh energy (4P4S) - that's enough to power all your devices and appliances.【Clean Energy & 50% Power Savings】LiTime 12V 300Ah LiFePO4 battery is an investment that will pay off in the long run. With a lifespan of up to 10 years and 4000-15000 cycles times, our 12V 300Ah LiFePO4 battery produces a total of 15360kWh energy (3840Wh x 4000 cycles times = 15360kWh). That's enough to save you 50% on power fees compared to using utility power. Our batteries are ideal for solar systems, camping, and outdoor activities. With simple installation and reliable performance, you can relax and enjoy 100% clean energy while saving money on power.【1/3 Lighter Weight & Higher Energy Density】LiTime 12V 300Ah LiFePO4 battery is a clear winner in battery weight and energy density. It weighs only 1/3 of a comparable lead-acid battery with the same capacity, making it easy to handle and transport. Plus, the battery's energy density is an impressive 61.14Wh/lb (3840Wh / 62.8lb = 61.14Wh/lb). That's almost twice as much as comparable lead-acid batteries, which provide only 29.53Wh/lb (3840Wh / 130lb = 29.53Wh/lb). 【Fast Delivery & Exceptional Customer Service】Enjoy fast delivery and exceptional customer service with LiTime. Our batteries are shipped from local warehouses in Los Angeles or Dallas and come with easy-to-understand operation manuals and online services. Our team is available to provide feedback within 24hrs.● DO NOT use as Starter Battery: This battery is NOT suitable for starting engines. If you need a starting battery, please consider LiTime 12V marine starting batteries series.