Sodium batteries are irrelevant, as they have no advantages over lithium batteries (except maybe a slight cost decrease). At the same time Japanese engineers prototyped magnesium-ion batteries, which will double capacity of Li-Ion:<p><a href="http:&#x2F;&#x2F;www.japantoday.com&#x2F;category&#x2F;technology&#x2F;view&#x2F;japanese-team-develops-high-energy-density-magnesium-rechargeable-battery" rel="nofollow">http:&#x2F;&#x2F;www.japantoday.com&#x2F;category&#x2F;technology&#x2F;view&#x2F;japanese-...</a><p>Can&#x27;t wait to see them entering mass production.