Tesla has had a bit of a rough year. Sales are way down, their stock is performing horribly, and a woeful Robotaxi rollout has tarnished the sheen of their AI self-driving push. It seems like every aspect of Tesla’s business is in decline — that is apart from one. Their grid-level energy storage is the only part of their business that has boomed over 2025, with sales increasing by over 67%! Some are even asking if such monumental growth could save Elon’s pathetic arse. Well, don’t count on it, because Musk’s nemesis, BYD, has just delivered a slam dunk on Tesla’s grid energy storage ambitions.
So, if Tesla’s grid battery business is growing, they must have some damn good batteries, right?
Well, their latest Megapack 3 seems impressive. Each unit is the size of a 20 ft container, which makes it easy to transport, and contains 5 MWh of battery capacity, for a price of around $1.3 million. Now, Tesla did plan on using their in-house designed and produced 4680 cells for this, but they have turned out to be a bit crap, so instead they opted for giant 2.8-litre LFP prismatic cells from China’s CATL. Because they use LFP technology, they have a lifetime rating of 10,000 charge cycles! As such, the lifetime cost per kWh stored is only around $0.026.
These figures are impressive. In 2020, grid-level energy storage was estimated to have a lifetime cost of around $0.15 per kWh stored. So the Megapack 3 represents a serious improvement.
Unfortunately, its success is dwarfed by BYD’s recently announced HaoHan energy storage system.
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