Select with Flexible warranty offer of 24 or 36 months. Refer to Our warranties Policy before making a purchase under this offer. Yokohama Platinum Batteries are backed by years of research and development and a thorough understanding of consumers’s needs. Yokohama batteries has calcium in both positive and negative grids, thus making it full calcium. Calcium strenthens the plates which gives the battery a longer life. Calcium also reduces the gassing caused by reaction between active material and electrolyte thus corrosion is minimized.