Maximum capacity of RAV4 EV's battery by design???

As we all know, the RAV4 EV's battery pack was designed and manufactured by Tesla Motors. Also, we know that Toyota rates the battery at 41.8kWh maximum "USEABLE" capacity after an extended charge. What we don't know is the Tesla's battery maximum "design" (spec'd) capacity. I think it surely must be greater than Toyota's specified "useable" capacity, but exactly how much more? 45kWh? 50? 60?

Does anybody know the actualy battery spec in terms of its "as designed" maximum capacity?

Dsinned said:

As we all know, the RAV4 EV's battery pack was designed and manufactured by Tesla Motors. Also, we know that Toyota rates the battery at 41.8kWh maximum "USEABLE" capacity after an extended charge. What we don't know is the Tesla's battery maximum "design" (spec'd) capacity. I think it surely must be greater than Toyota's specified "useable" capacity, but exactly how much more? 45kWh? 50? 60?

Does anybody know the actualy battery spec in terms of its "as designed" maximum capacity?

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First, let me say that new early LEAF owners had the same wide eyed wonderment. Was this super duper 24kWh battery really 28.8kWh (a common number pulled out of their posterior) or some other fantastic magic? It wasn't, and it ain't magic.

As I stated in another thread, I believe that 41.8 kWh is the advertised capacity, much like 24kWh is advertised for LEAF. In government funded lab studies, we find that 21.3kWh is actually available at room temperature. From my Nissan LEAF days, where Nissan nonchalantly tosses around range and battery capacity like jam on toast, I find it best to "trust but verify" these claims.

I've done two runs so far to near depletion. Last night, Itook it all the way to turtle (see photos posted in the other thread). I estimate 37.6kWh useable at 100% charge (extended range) and 30kWh at "normal" charge (about 80%).

Naturally, I would love real laboratory data, but if the LEAF experience taught me anything, it will be a rough road getting there.

Seems reasonable to assume Tony. Toyota ought to publish this information. Instead of referring to "useable" capacity, Toyota would be more accurate referring to the "actual" (or full spec) capacity of the battery as 35kWh after an 80% standard charge, (or 41.8kW, after 100% "extended" charge).

In actuality, I suspect Tesla's very expensive battery pack SOC is never allowed to be fully depleted to absolute ZERO by design; not even close!

A very low battery charge depletion threshold is probably based on some measurable decrease of the battery's terminal output voltage. This is pure speculation, but that might be at a lower limit threshold of say 350VDC, ~10% decrease from a nominal (healthy battery), fully charged, terminal voltage of 386VDC. To allow it to go much lower than say -10% of nominal, (as in a deep discharge situation), could seriously degrade or damage the battery. A lower voltage might not even be enough to overcome counter EMF interia to drive the AC induction traction motor under full load.

Dsinned said:

A very low battery charge depletion threshold is probably based on some measurable decrease of the battery's terminal output voltage. This is pure speculation, but that might be at a lower limit threshold of say 350VDC, ~10% decrease from a nominal (healthy battery), fully charged, terminal voltage of 386VDC. To allow it to go much lower than say -10% of nominal, (as in a deep discharge situation), could seriously degrade or damage the battery. A lower voltage might not even be enough to overcome counter EMF interia to drive the AC induction traction motor under full load.

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The LEAF is 393.5v fully charged (96 cell pairs multiplied by 4.1 volts per cell), and at 17.4%, which is "Very Low Battery" and also the "voltage knee" of the battery, occurs at about 350 volts. It quickly drops to about 300 volts, where it enters "Turtle mode", and battery cutoff leaves 2% at the bottom, at about 295 volts.

I suspect our Rav4s are quite similar.

For now, the Rav4 EV will be powered by a Tesla-built lithium metal oxide battery that has a usable output rated somewhere in the mid-30 kilowatt-per-hour range. The battery was built and supplied exclusively by Tesla for the Rav4 EV, among other parts.