It's been a while
since we've had
a chance to step back and describe the status of this project. Some
people have
been working incredibly hard to make this happen, while others have
been
wondering "when will complete plans and kits be available?" The
bottom line is that we're getting much closer! A couple of the most
adventurous
people already have DIY conversions running, and others have started on
theirs.
This entire project
has
essentially been done by volunteers, and we've always been
short-handed. Here's
a summary and an invitation to get more deeply involved.
One immediate point
I’d like to
make that bears on the value of this discussion group and why many
people may
have been wondering if anything has been happening: There
have been many private conversations
among several parties (me included) pertaining to conversion specifics,
control
board specifics, etc. I would like to
encourage us all to migrate these conversations, except those that
really are private between 2 or 3 people, to
here. If that ends up overloading this
discussion group (as it may, since it also carries general discussions about conversions), we’ll start another group
just for technical implementation discussions.
DOCUMENTATION:
Chris Ewert is one of
the first
two people to have completed a CalCars/eaa-phev DIY conversion (Kurt
Jensen of
Nilar is the other; the rest have been done with my supervision). Chris has been working extensively on the
do-it-yourself (DIY) documentation, which we believe has now reached
the point
where an electronics- and mechanics-knowledgeable person can do a
conversion
with little external hand-holding. To see the current state of
documentation, go
to < http://www.eaa-phev.org/wiki/PriusPlus>
and click on the various sections at the top:
Theory | Step-By-Step
Instructions
| Parts List | RawData
If you would like to
help with
this effort, please email Chris at <chris@...>.
BATTERIES, BOXES, AND
WIRING:
PbA: We
have a new PbA battery box, designed by
Robb Protheroe <robb@...>, who will be selling
pre-fabricated
boxes for a modest price. This steel box
with a Lexan cover will solidly mount the 20 EVP20-12s and all
electronics
except the charger. It hinges and easily
lifts using gas shocks for access to the spare tire! The
first units should be available around
the September time-frame. The PbA
modules weigh 280 lb, provide 10-12
miles of EV range, last 200-400 cycles (1-2 years), and cost around
$900 from <http://www.electricrider.com>
(tell Dave at Electric Rider that you are doing a CalCars conversion). We are expecting to document a wiring harness
for this conversion, and hopefully fabricate harnesses to be sold at a
reasonable price, thereby greatly speeding the conversion process.
NiMH: Robb
has designed a similar box for the Nilar
NiMH modules <http://www.nilar.com/index.php?pageID=33&languageID=1>
that
are becoming available in limited quantities, and we are working on the
add-on
BMS board that will be needed with them.
27 or 30 modules (we don't yet know which quantity is best)
should
provide 20-25 miles EV range, weigh around 230 lb, with an expected
cycle life
of up to 2000 cycles (6 years of daily use) and an expected cost of
$6-7k. (Though our Electro Energy conversion
was
done first, we do not yet know if modules will become available from
them for
further conversions.)
Li-ion:
Among other possibilities, we are about to
begin testing on (2P4S) modules made from 11Ah large-format Li-ion
phosphate
cells by PSI (http://mvp090-1.104web.com.tw/cetacean/front/bin/home.phtml). We'll let you know as this progresses.
Its potential pricing and range is similar to
Nilar's with somewhat lower weight but requiring a more sophisticated
BMS (see
under chargers, below).
CONTROL BOARDS:
The first turn of the
new control
board I was working on, not totally unexpectedly, had a few bugs, so we
are
doing a second version of its layout. We
have taken advantage of this to expand its capabilities as follows:
Chris Ewert has
designed a
microprocessor-based version of the circuits that handle OEM and PHEV
battery
heating and cooling. This has been moved
off the base control board and onto a "Temperature" daughterboard
that plugs onto the base "Control Board". The
Control Board will be capable of
functioning without the Temperature Board (e.g. if needed for
debugging),
except that battery heaters and fans will not be powered.
The new Temperature Board will help optimize
PHEV operation in the low- and high-temperature weather that Chris has
encountered in
* The Control Board
will now
accept multiple layers of daughterboards, with force and inhibit
signals added
and passed between the boards, to handle BMSs for various battery packs
--
including Nilar, Electro Energy, and PSI -- as well as future
situations we
haven't thought of yet. We believe that
it will also be applicable to conversions of other
* The driver-visible
LED panel has
been simplified and (hopefully) made more clear in meaning.
* To make testing and
debugging as
easy as possible, a Test Board will be available that will plug into
the same
sockets as a daughterboard. We will
write test procedures to go with it.
* The down side to all
this is
that Control Board and Temperature Board PCBs will probably not be
available
until September. However, all is not
lost! Chris Ewert developed an Interim
Control Board that does the minimum work necessary to run a conversion
pretty
well as a PHEV. He ordered a run of 50
PCBs, which are available now for $14.50 each, including shipping, at
<http://www.uninterruptiblesolutions.com/priusplus-temporary-backup-control-board-p-179.html?zenid=d93e3d34982c07b8ff452c9050eecb8e>.
CHARGERS:
* Chargers are
currently our
biggest concern. Everything currently
available is for PbA and has one or more problems:
* Delta-q has been
amazing at
supplying CalCars with prototype PHEV chargers, and its chargers are
very nice
small, efficient units that are expected to sell for a modest $800 or
so. Though production is not slated to begin
until early 2008, prototype units may be obtainable. However,
the charge control algorithm
currently in use (Delta-q chargers can be field-reprogrammed) appears
to
significantly overcharge the pack. We
don't know when this issue will be resolved.
* ZiVan chargers are
also
similarly priced. The two issues are
that each unit must be custom programmed at the factory to allow a
current
limit low enough to not blow a 15A 120V circuit, and the power factor
is low
enough that charge current is more limited than necessary, thereby
lengthening
charge time.
* Brusa makes an
excellent
user-programmable charger, the NLG3-lite, available at <http://www.metricmind.com/charger.htm>. The downside is its $2600 price.
* For around $2k, one
can also get
a Manzanita Micro PFC-40 (40A!) charger.
On the downside, it is not line isolated, so more care must be
taken to
keep the battery pack itself isolated.
On the upside, it can double as a DC:DC converter between the
PHEV and
OEM battery packs, allowing more flexibility in PHEV pack voltage and
other
advantages (CalCars has not created a design that does that, but this
charger
is used in that way in the PiPrius conversions <http://www.eaa-phev.org/wiki/PiPrius>.
* I am working on a
charge
balancing/BMS that will also double as a charger. I
plan to make versions available for PbA and
Li-ion packs, but maybe not NiMH, due to technical limitations
involving NiMH
end-of-charge characteristics. Parts
costs should be around $500-1000. For a
long time I have not had time to work on this, but it appears to be
getting
more and more critical to the success of conversions.
CONVERSION KITS AND SERVICES:
Several people have begun or are about to begin businesses to sell fabricated components, kits of components, and/or conversion services. You can check the list at http://www.calcars.org/howtoget.html. Here, however, are a couple of new players not yet on that list and specifically focusing on the CalCars/eaa-phev conversion system:
* Robb Protheroe <robb@...>: pre-fabricated battery boxes and maybe more
* Chris Ewert <chris@...>, http://www.uninterruptiblesolutions.com/priusplus-temporary-backup-control-board-p-179.html?zenid=d93e3d34982c07b8ff452c9050eecb8e>: CalCars/eaa-phev conversion's custom printed circuit boards
* Kim Adelman
<kadelman@...>, http://www.pluginconversions.com/:
conversion services using Nilar NiMH modules, starting with three
conversions Aug 15-31.
* James Philippi
<philippi@...>, http://www.pluginconversions.com/:
conversion services and maybe kits
EAA-PHEV NEEDS
VOLUNTEERS &
PROJECT MANAGER:
Last but not least,
I'd like to
discuss the future of the DIY PHEV project.
Eaa-phev.org developed as a collaboration between the Electric
Automobile Association <http://www.eaaev.org>
and CalCars <http://www.calcars.org>
to support experimenters in converting hybrid automobiles into PHEVs. CalCars has put its designs and knowledge
into the public domain at http://www.eaa-phev.org/wiki/PriusPlus
as a starting
point, and I have worked with a small group of very dedicated people to
expand
this knowledge into a documented, buildable DIY Prius conversion (I
sent Chris
a thumbnail history of this process that will hopefully be added to the
documentation somewhere). This stage is now
nearly complete, several
conversions have been done, and the status is as I explained above.
We would now like to
expand the
project into more of a Linux- or gnu-like open source project, with
many
converters and other knowledgeable people jumping in to provide further
documentation (which is already in a wiki, created by Ryan Fulcher),
enhancements, kit parts, conversions for other hybrids, etc. To do this without it becoming a free-for-all,
we are looking for an open-source Project Manager who can organize and
coordinate such an effort, help formulate goals, request and/or accept
sub-projects, provide collaborative tools that we may be missing so
far, and
help ensure some level of accuracy and consistency. Please
contact me or Chris if you would like
to be considered for that role.
-- +++++++++++++++++++++++++++++++++++++++++ Ron Gremban, rgremban@... California Cars Initiative, a nonprofit organization: http://www.CalCars.org Moderator & Technical Lead http://www.priusplus.org PRIUS+ PHEV Conversion Group: http://groups.yahoo.com/group/priusplus Newsletter: http://groups.yahoo.com/group/calcars-news Do-it-yourself PHEVs: http://www.eaa-phev.org/wiki/PriusPlus +++++++++++++++++++++++++++++++++++++++++
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