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Eco Battery looks to be a pretty solid player lately on the lithium pack front, but I noticed one of their latest additions, a "72v" battery, is actually only using 22 cells -vs- 24 cells used by all the other solutions I've seen available.

They list the nominal voltage as 70.4, so they aren't hiding this fact by any means, but the model number is 72xxxx and it is being referred to as a 72v battery. It's close, but there is a difference in that it is around 6.6v lower in total than the other (Extreme team, custom, RoyPow, etc...) 72v LifePo4 24 cell solutions.

I emailed to make sure I had this right, and they verified it was a 22 cell pack, and their reasoning makes some sense - it is because high regen, plus high charge levels, plus hilly terrain may make for situations where voltages get too high and they mention that controllers could potentially be damaged in such situations.

RoyPow includes a resistor as their solution, but is actually a 24 cell pack. I think Extreme Team is just a straight 24 cell pack, w/out any special accommodation for potential excessive voltage.

These batteries are often paired with the Navitas controller / motor, which is spec'd as being compatible with 72v.

Performance wise, I'd expect the Eco Battery "72v" unit to very slightly under-perform when compared to 24 cell packs, but in use cases where regen settings are high, and / or driving is in hilly terrain, at times with near-100% charge states, it could provide a safety buffer other solutions (except the RoyPow) might not offer.

Would also allow their pack to be a tick lighter I would think.