On 03/27/2015 12:50 AM, EVDL Administrator via EV wrote:
On 26 Mar 2015 at 19:57, Ben Goren via EV wrote:
That's the idea behind my suggestion of a "remaining (usable) kWh"
gauge ...
Sounds good to me.
Solectria had a simple answer to this. They gave you a straightforward amp-
hour meter. As you drove, it counted up; as you charged, it counted down.
When the charger shut off, it zeroed itself.
After a few years driving my conversion with a TBS amp-hour counter, I
was expecting something as straightforward in my Leaf. I don't know how
modern factory EVs estimate the battery capacity but on the conversion,
I felt the need to do the occasional "capacity test". I would fully
charge and balance and then pull it down until some cells started going
low. I reported the tests here amid quite a bit of scepticism. My
260ah ThunderSky LFP cells started off giving me about 300ah. They
smoothly declined over the years and are currently about 230ah. I was
expecting similar or better performance on the Leaf battery. I was
sorely disappointed. The conversion went about 50 k miles over about 7
years and suffered about 20% capacity loss from new (a bit more than 10%
from advertised). While the Leaf lost 30+% in two years and 20k miles.
Both batteries endured the horribly hot summer (about 100 days above 100
deg) that so damaged the Leaf battery. The ThunderSkys seemed unaffected.
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