PHEV Conversion

What I'd like to see is a simple Parallel connection to the existing HV battery to another HV pack of the same voltage, stored above the spare tire.
Removing the spare tire.

If a recycled HV Prius battery is 1/4 the cost of a new, and could be stored (with perhaps some modification to it's size) and hooked in Parallel, effectively doubling the amperage.

With a Shunt, the extra pack could be plugged-in, unplug and shunt-on to double amperage. No voiding of the warranty.
Because it's another NiMh pack instead of LiOn, no need to reprogram the car's computer. The drain will simply take longer to occur.

In any case, even if GM's Volt is a failure, it will usher a new battery pack designed for EV cars, and that battery company will have an instant market with over a million Prius on the road.

 

im curious what was the cost of all those things?

 

http://priuschat.com/My-official-Prius-Plu...ead-t26951.html

 

<div class='quotetop'>QUOTE(Mark Derail @ Oct 5 2007, 03:01 PM) [snapback]521896[/snapback]</div>

This is pretty much everyone's first idea when thinking about PHEV (including mine)

Unfortunately its more complicated than that. What you are talking about can be done (and has been done) but it has minimal effect. Basically the toyota programmed battery controller is too smart. The key to successful conversion is how to trick the toyota software to recognize and use the additional battery capacity (unless you completely replace the battery and create your own controller).

The calcars conversion method is basically the simplest way to accomplish this. Use a big relay (contactor) to connect and disconnect a big battery pack to the main oem battery. Use a controller (CAN-View) to monitor the oem battery and driving conditions and decide when to connect and disconnect the extra pack. Make the extra pack voltage high enough that when connected the oem pack senses the high voltage and recalibrates (SOC drift). Play a few tricks with fans and warmers to try and keep the battery in the right temp range to use EV or assist as much as possible. Charge up the big battery overnight so its full every morning.

There are more elegant ways to do it, that will maximize range and efficiency but they are much more complicated and expensive.

rob

 

<div class='quotetop'>QUOTE(ibcs @ Oct 5 2007, 02:39 PM) [snapback]521889[/snapback]</div>

Is it practical? Probably not. Using NimH or Li-ion the cost today for a private individual is well beyond what you will recoup in gas savings. Lead acid has much lower upfront cost, but due to expected 1-2 year battery life, lifetime ownership cost may actually be worse than NimH or Li-ion. On top of that this is not a mature process. Unless you can pony up $20-30k for a commercial conversion, there will be a lot of fiddling, tweaking, and monitoring involved for the foreseeable future. Down the road when these professional conversions are $5-10k then we may be talking.

All that said, I can't wait to do mine! The motivation to do this has to be other than financial. For me its part engineering challenge, part desire to reduce carbon footprint, part desire to reduce foreign oil consumption, and part saying a big screw you to the "man" (oil companies, auto companies, government etc).

High amp marine batteries would be great, except for the weight. The smallest I have found are Optima D51s at around 26 lbs. This is still really heavy, given that you need 20 of them. They are also considerably less efficient than their larger brothers the D31s and D34s. Even a D51 pack with one passenger would place you at GVW limit for the vehicle, maxing out the suspension, reducing efficiency due to extra weight, and potentially creating a crash hazard. Most people seem to be targetting a battery pack around 200-300 lbs as a good compromise between range, safety, handling etc. This puts you in the 10-15 lb battery class, the best of which are probably high output, high cycle UPS batteries.

This is one advantage to the Manzanita Micro PiPrius approach, of using a dc:dc converter between the supplemental pack and the main pack. Then you can use a smaller number of larger more efficient batteries. Of course this approach ads significantly to the project cost.

Definately check out the thread rock posted, you'll find a lot af great details Cheap has posted on his conversion process. You may also want to spend some time researching on http://www.eaa-phev.org/wiki/Prius_PHEV home of the open source calcars conversion.

Good luck!

Rob

 

I like the idea of a relay to go from one HV to another.

When at rest it's the OEM battery, so the extra HV is always disconnected when the car is at rest. An extra relay triggered by 120VAC plug-in as a security measure on the same line.

I also like the DCC conversion. Less batteries would mean that the newer higher voltage batteries could totally replace the OEM battery pack.
In my case going from EV-2 to EV-10 would make a huge difference in gas usage.

 

<div class='quotetop'>QUOTE(Mark Derail @ Oct 8 2007, 11:51 AM) [snapback]522729[/snapback]</div>

Ain't as easy as a relay switch over between batteries.

Make a deeper search in PriusChat and google to find out the strategies and moneys involved on PHEV conversions.

 

To be honest, my motivation is not to save money. It would be nice, but my theory is that I can enhance a nice vehicle to get 90+ miles to the gallon For few extra miles. How about the environment?

I guess my motivation is the desire to not use gas. In that case, you should go for solely an Electric Vehicle, certain versions are more economic than a Prius.

Sounds stupid, but I guess I'm turning GREEN and want to be the first in my area.

I read the thread, but the problem I had with the thread is it does not tell where to buy the parts ( you have not read or research the threads deep enough to assimilate the information provided ) and/or if they can be bought as a kit. Your first already starter kit will cost you about $7200.00 at Manzanita Micro with out batteries, obtainable locally to avoid heavy shipping fees.

If you want to sprint for a CalCars DIY lesser principal investment to save some bucks, be ready to learn how to assemble PCB, wiring harness and willing to deal with harmfully some times lethal High Voltages at DC levels.

That was my purpose of starting the thread. Honestly, 4K for a 2K return in gas savings would not offend me.

 

wow... after a lot of soul searching (yes there ARE other issues besides saving gas money!!...) and a lot of thinking, weighing options, etc.

i dont think a viable plug in option is available so i have decided to just purchase another vehicle instead for the 80% of my driving needs that a low speed, limited range EV would provide.

before this decision, i said i would pay $10-15,000 to get 30 miles of all EV range. well. looks like nothing even romotely close to that is going to happen, so i went a bought an EV that gives me that for $14,500.

only time will tell if it was a good decision, but in the interim, i can feel much better about myself and the small role i will play in hastening acceptance of EV transportation

 

Zenn 2.2 EV

it does 35 mph, has estimated range of 40 miles on upgraded battery pack. i hae come to the conclusion that just as the Prius became popular, low speed EV's will only become popular when the money starts flowing its way...so i am helping to increase the flow.

people will ask, i will tell, some will follow.

fact is, no one follows pictures and articles about products that are perpetually 2 years away

 

"Is it practical" turns on how thick your wallet is.

 

<div class='quotetop'>QUOTE(hill @ Oct 9 2007, 09:29 AM) [snapback]523146[/snapback]</div>

maybe so, but we will never get innovation if the money aint there.

i know i am on the bleeding edge of this. i predict HUGE government incentives to buy an EV. missing that.

i am making sacrifices, conceesions, etc... that is a given. but will it be a waste of money? if it falls apart in 2 years, ya probably, if i can not go where i want because a hill is too steep (and there is a LOT of hills to climb here... most are avoidable and my current commute route is flat so ya, i am in a situation that will not work for many) yepper... but will i feel good about trying? oh hell ya!!

i want tto be asked about my car!! i loved it with the Prius, i hope i will be as enthusiastic about the Zenn as well. i think i will be ok. only time will tell and i feel lucky to be in a position to be able to try the Zenn. the Zenn will partially replace a 1988 Toyota Corolla which will go to someone who will be using it as his main transportation vehicle for his daily 50 mile commute parking his 14 mph pickup so ya, it will make me feel good and in this world, that is my main goal in life.

but for every EV on the road, you will have 200 people who will notice, 20 will care enough to ask, 2 will follow.

all i can say is dont underestimate the power of 2

 

<div class='quotetop'>QUOTE(ibcs @ Oct 5 2007, 01:11 PM) [snapback]521905[/snapback]</div>

Yeah, double one mile of EV to a whopping two... Woo hoo! LOL. As an EV solution, no way. But you may well see some mileage benefits.

 

<div class='quotetop'>QUOTE(ibcs @ Oct 9 2007, 08:24 AM) [snapback]523068[/snapback]</div>

As i understand it, the benefits of the dc:dc converter are mainly:

1. Output voltage more constant over discharge. Normally, direct connected batteries tend to sag as they discharge and are less and less effective as they do so. This limits the effectiveness of the bottom half of the pack. You don't necessarily want to discharge the pack down this far anyway though, as you'll start reducing the pack's life expectancy.

2. Some larger batteries are of higher efficiency than what is available in smaller batteries. When you do not have to get up to 240V battery pack, you are free to explore these larger batteries.

You never get something for nothing though. If you cut back from a 240V pack to a 120V pack, you need to at least double the Ahs of the pack to keep its energy capacity the same. For example, in order to put out 60A at 240V, the battery will have to put out 120A at 120V. This will draw it down twice as fast, so you need a bit more than double the capacity. Since the current draw is higher, the ideality factor (peukerts number) becomes far more important. Unless you are going to go with a real high end 120V pack (such as Optima D31Ms, or Orbitals) it may be hard to outperform a good 240V pack.

Here are a few examples (Note prices are internet, may vary, and don't incl shipping)
Battery-----------Pack---Volts----Weight---Cost----Time/Amps-----Ceff (kWh)----Wh/lb---Wh/$
CSB GP12200---1x20----240------282----$725----9.67min@60A------2.32---------8.22-----3.20
BB EVP20-12----1x20----240------286----$1040---11.0min@60A------2.64---------9.23-----2.53
Yuasa NPX-80---1x20----240------290----$1240---12.3min@60A------2.95---------10.2-----2.38
Yuasa NPX-100--1x20---240-------416----$1950---18.1min@60A------4.34---------10.4----2.22
Ody PC925------1x10----120------260----$1180---9.42min@120A-----2.26---------8.69----1.92
Optima D51------1x10---120-------260----$1390---11.8min@120A-----2.83---------10.9----2.03
Ody PC1200-----1x10----120------382----$1488---13.3min@120A-----3.21---------8.39----2.15
Optima D34------1x10----120------384----$1800---21.6min@120A-----5.18---------13.4----2.88

So for this dataset, the Optima D34s seem to be the only batteries with a significant advantage over the smaller packs.

Rob


<div class='quotetop'>QUOTE(ibcs @ Oct 5 2007, 06:55 PM) [snapback]522002[/snapback]</div>

Then you may be a good candidate for a calcars conversion. I think in the next 3-6 months they will have this thing ironed out and packaged up in a user friendly way. They would have probably been there by now, but there have been some recent changes in strategy that will make it more effective in the long run.

If you want to move ahead sooner than that, I would try and hook up with someone like Cheap who has already done one, and knows how to fill in some of the remaining gaps.

rob