The starter and permanent battery are specially designed for watercraft. The Optima battery was developed by Denver Gates Rubber Company engineers in the early 1970s on behalf of NASA as part of a space program. The requirement was a small, high starting current, leakage and vibration resistant power supply. Today, Johnson Controls Inc. is manufactured. The factory in Colorado Optima batteries for 3 different applications. Optima battery is based on SPIRACELL TECHNOLOGY spiral technology – a registered trademark. 114/5000 The Optima battery consists of 6 jars made of impact-resistant plastic with spiral elements. Each element consists of a tightly compressed + and – plate with an electrolyte-impregnated glass fibre separator between them. The elements are connected by intermediate bridges, one of which acts as a fuse in the event of a short circuit. The battery is sealed by laser welding with a cover containing spark-proof pressure relief valves. Charging Optima batteries: The Optima battery has very little self-discharge. However, if the voltage drops below 12.3V, the battery must be charged with a voltage of 14.2-14.5V When charging with high current (20A and more), a significant reduction in charging time must be taken into account. The Optima battery is charged when the terminal voltage is 12.83V for starter batteries and 13.8V for permanent batteries. Voltage 12V Capacity 66Ah Starting current 845A Terminals: – / + Length 308 mm Width 175mm Height 220 mm Weight 24.4 kg