# [EVDL] First impressions TS LFP160AHA @144V



## EVDL List (Jul 27, 2007)

Hi EVerybody. I've been away from the list for quite a while due to
other pressures, but I thought I would post an update to my ev projects.

I've been in touch with Doug Hartley and through him got 45 TS
LFP160AHA Li-ion cells. The plan is to put them into a 2006 Scion xB
which I picked up last fall from a guy on Ebay. This is a nice little
car at a nice price with lots of room for dogs and groceries. It
handles well but is not much fun on the highway because of engine
noise. Well, it made its last highway trip last week when I drove it
up-island to Errington BC where Randy Holmquist is going to convert it
for me. I just don't have time to do another conversion, and although
Randy is getting out of the conversion business, I managed to talk him
into it. He did a nice conversion on an Echo a couple of years ago
and a when he had a preliminary look at the Scion last month he
commented that it should be easier since there is much more room in
the engine compartment.

I've been sitting on the TS cells since November. Between work and
frequent trips to Victoria to look after my Mom's estate I have had no
time to play. I planned to install the TS cells in the Mazda B2000
whose pack had finally been retired to the scrap yard so that I could
gauge what kind of performance I could expect with a relatively low
voltage pack of li-ions in the Frozen North. I finally got them
hooked up a couple of weeks ago and have had a few days experience driving 5km
to work and back, with occasional added on shopping trips.

I'm using Stybrook charge controllers which have low and high voltage
signal outputs and an led-resistor combo that can waste 250ma. They
came factory set to turn on at 4.15V or so but I found that they were
not all the same out of the box. I've spent a few hours
adjusting them so that they come on near 4.00 volts. As
of this morning, the resting voltages of the "fully charged" cells
were all 3.8xx. I have been boosting the low ones and shunting the 
high ones until they all read 4.00 to 4.07 volts at less than 0.5 amps 
at end of charge.

It seems like
there is a learning curve with these cells. I hope I don't destroy
them like I did with my first set of floodies. Doug has been very
helpful giving me advice, and I have spent several evenings hovering
around the pack with a voltmeter while it is charging.

Two of the Stybrook modules are dead, probably due to carelessly
installing them reversed for a few seconds (doh!). One of them 
actually came back to life when I touched the transistor yesterday. 
Perhaps it has a bad solder connection. Something to check in the 
near future.

I made up some 24 Ohm shunts from some 2W resistors I had lying around 
and have kept a close eye on the two modules to keep them from 
overcharging.

On the road, the no-draw voltage is ~156, and under a 200amp load it
drops to ~137. I have heated underground parking at the condo, but at
work I park in an unheated open structure. This week the outside
temperature has been -15 to -20C. I have not had time to properly
insulate the pack - just put some styrofoam around it and a sheet of
plywood on top. At the end of the day the resting voltage drops to
146, 144 with the heater on, and 130-135 under load of ~100 amps. I
have had to drive the way I did with the nearly dead flooded pack I
had been nursing for the last 6 months at 96 volts. Time to get some
serious heat and a real box for these beauties. Although they are
terribly soft when cold, they just keep going and going. I have not
yet really put them to the test - waiting for a few more gentle cycles
and more balancing. Also, I must hook up the low voltage warning
signals so I can have a better idea what is happening under load.

** I wrote the above a week ago and for unknown reason it never showed 
up on the list (unless it just did and I haven't read that digest 
yet!). Since that time I made a better box and the batteries keep 
warmer and perform better at the end of the day. My biggest draw was 
just under 100Ah and they were still behaving well. Unfortunately, 
the truck has some new mechanical problem, a vibration at high speed 
that I have not figured out yet. It seems to be more related to high 
motor speed rather than high wheel speed. I need to figure that out.

Mike Hoskinson
Edmonton






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