Honda plans to produce solid-state batteries for electric vehicles that can reach 1,000 kilometers on a single charge – more than double the range of electric cars currently available on the market.
As solid state batteries they use a solid electrolyte, which allows the movement of ions (but not electrons) between the electrodes – cathode and anode – of a battery. This generates electricity by forcing electrons to circulate through an external circuit.
These batteries are more energy dense because they can use pure lithium metal anodes, which store more energy in less spaceinstead of graphite anodes used in liquid batteries.
Furthermore, they do not require strict temperature control and are saferas they do not use flammable solvents such as ethylene carbonate, common in liquid electrolytes.
In November, Honda revealed a demonstration production line for its future solid-state batteries, which the Japanese automaker plans to integrate by 2030.
“The solid-state battery is an innovative technology that will be a game-changer in this era of electric vehicles. Replacing the engines that have supported automobile advances to date, batteries will be the key driver of electrification,” he said. Keiji Otsupresident and representative director of Honda R&D, in a .
As detailed by , these solid-state batteries are expected to be 50% smaller, 35% lighter and 25% cheaper to build than the liquid lithium-ion batteries present in current electric vehicles.
It is also estimated that Honda will have its long-range solid-state batteries in its cars by 2030. By 2040, Honda has set a goal that its electric cars will have solid-state batteries with a autonomy of 1,249 kilometers.
This is expected to be a major step towards overcoming the widespread problem of – one of the main barriers to the adoption of electric vehicles.
It is urgent to overcome barriers
The main obstacle to this technology is the fact that the solid-state cells that Honda has developed to date are too small to be used in any current vehicle model.
In fact, technical challenges continue to prevent lithium-ion batteries from being reliable enough for electric vehicles.
The biggest problem is the fragility of the ceramic separatorused to prevent the anode and cathode from touching, which can begin to crack over time due to expansion and contraction caused by chemical reactions.
As Live Science explains, if this happens to the separator, which is also the solid electrolyte, it can cause a short circuit between the electrodes and cause battery malfunction.
Another problem is that the electrolytes in solid state batteries are made of polymers, which do not allow the flow of ions between the electrodes as easily as in a liquid electrolyte, thus limiting battery performance.
Additionally, over time, the electrodes on these batteries may become coated with spiky lithium depositsknown as dendriteswhich can pierce the solid electrolyte, causing a short circuit in the batteries.
