Hello all!
Back from the summer holidays. There really is a heavy Thunder Sky
bashing going on here. The picture that you get from most of the
stories is quite gloomy, both technically and businesswise.
I don't know about their way of making business, but here are some
technical experiences as a user.
Since March 2007 I have been driving a Subaru Elcat, equipped with
ThunderSky batteries and a BMS from Jukka.
The original Subaru Elcat has a lead-acid pack, 78 V, 180 Ah, 416 kg.
Range is something like 50 km.
The lithium pack is 80 V, 350 Ah, 312 kg pack, built of 24 ThunderSky
350/400 Ah batteries.
I have made almost 6000 km (4000 miles) now, which comes mostly from
commuting to work. My total commute both-way is 76 km (47 miles),
which
distance I can now make very well without charging at work. Although I
charge at work anyway, maybe once or twice a week. This is because the
car's charger is only 1.6 kW and charging only at home at night is not
always sufficient.
The average drive per charge might be something like 60 km (37 miles).
This means that I have made some 90-100 charging cycles with the
batteries now. No change in battery behaviour or capacity degradation
has been observed.
Range figures: My normal consumption for the one-way commute is very
close to 100 Ah, which gives: 100 Ah/38 km = 2.64 Ah/km. Energywise it
makes 2.64 Ah/km * 80 V = 210 Wh/km = 340 Wh/mile.
Mathematically you get for the range: 350 Ah / 2.64 Ah/km = 132 km =
82 miles.
I have never tried to test the maximum range, but my longest drive on
one charge has been 110 km (68 miles), and there was yet no sign of
nearing the limit, only the cell voltages started to sag a bit.
Normally the cell voltage stays between 3.1-3.3 V depending how heavy
foot you have.
Note also that approximately one half of my commute is done with the
accelerator floored (the top speed of the Elcat is 85 km/h (53 mph)
which just barely lets one keep the normal road traffic rhythm, and
not
even that at up-hills
. So with a little lighter foot there should
be
no problem reaching 150-160 km (90-100 miles), and I think you can
make
even 180-200 km (110-120 miles) if you drive slowly and carefully.
I have been very happy with the batteries' performance. There is
tremendous difference to lead-acid technology, and also to NiCd
technology.
Seppo Lindborg
_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
Back from the summer holidays. There really is a heavy Thunder Sky
bashing going on here. The picture that you get from most of the
stories is quite gloomy, both technically and businesswise.
I don't know about their way of making business, but here are some
technical experiences as a user.
Since March 2007 I have been driving a Subaru Elcat, equipped with
ThunderSky batteries and a BMS from Jukka.
The original Subaru Elcat has a lead-acid pack, 78 V, 180 Ah, 416 kg.
Range is something like 50 km.
The lithium pack is 80 V, 350 Ah, 312 kg pack, built of 24 ThunderSky
350/400 Ah batteries.
I have made almost 6000 km (4000 miles) now, which comes mostly from
commuting to work. My total commute both-way is 76 km (47 miles),
which
distance I can now make very well without charging at work. Although I
charge at work anyway, maybe once or twice a week. This is because the
car's charger is only 1.6 kW and charging only at home at night is not
always sufficient.
The average drive per charge might be something like 60 km (37 miles).
This means that I have made some 90-100 charging cycles with the
batteries now. No change in battery behaviour or capacity degradation
has been observed.
Range figures: My normal consumption for the one-way commute is very
close to 100 Ah, which gives: 100 Ah/38 km = 2.64 Ah/km. Energywise it
makes 2.64 Ah/km * 80 V = 210 Wh/km = 340 Wh/mile.
Mathematically you get for the range: 350 Ah / 2.64 Ah/km = 132 km =
82 miles.
I have never tried to test the maximum range, but my longest drive on
one charge has been 110 km (68 miles), and there was yet no sign of
nearing the limit, only the cell voltages started to sag a bit.
Normally the cell voltage stays between 3.1-3.3 V depending how heavy
foot you have.
Note also that approximately one half of my commute is done with the
accelerator floored (the top speed of the Elcat is 85 km/h (53 mph)
which just barely lets one keep the normal road traffic rhythm, and
not
even that at up-hills
. So with a little lighter foot there should be
no problem reaching 150-160 km (90-100 miles), and I think you can
make
even 180-200 km (110-120 miles) if you drive slowly and carefully.
I have been very happy with the batteries' performance. There is
tremendous difference to lead-acid technology, and also to NiCd
technology.
Seppo Lindborg
_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
