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Technician1002
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Thu Jul 11, 2013 6:47 pm

At 170,000+ miles, my car needs more than a simple oil change and replacement tires and 12 volt batteries. Other than replacing the plugs at 120,000 miles, my car has been trouble free. I've not needed to replace brakes, lights, belts, pumps, anything.. Wow.. Never had a car that reliable ever. Due to regenerative breaking, the brakes still have over half the pads left. I've never had brakes go over 100,000 miles before.

Last week I started to get some codes.. The hybrid battery pack is due to be replaced. Searching online shows that they last an average of 150,000 to 200,000 miles. The replacement is on the way and due to arrive tomorrow. Today I ordered a pair of 1,000 volt rated electrical gloves. I plan on living through the replacement. I'll get some photos of the replacement if anybody is interested in this project.

I've been studying how to change it safely. I found they thought out the design very well. The 270 volt pack has a disconnect fuse in the center of the pack that splits it into 2 halves. The contactors disconnect both the + and - outputs, so with the fuse disconnect pulled, the split pack is floating electrically so unless you get in contact with multiple terminals inside the case, electrical hazards are minimal.

Because I have to open the pack and remove the battery ECU that monitors the pack to move it to the new replacement, the contactors, and wire harness, I ordered the electrical gloves. If I ordered a rebuilt pack, I could have avoided this ECU replacement as they come installed, but new packs come without them.

There has been an issue with the original batteries and corrosion on the terminals, so some of the work to be done will be to clean the original wire harness terminals before installing it in the new pack.

If I never post again, you will know that the swap went badly..

This is the huge expensive battery failure many Prius owners are afraid of. If you do the work yourself, the expense is not too bad. A new battery (not rebuilt) is $2,295 and I spent about $60 on the gloves. I have saved enough over 10 years in gas and other repairs that were not needed to pay for this repair. The reliability has been great.

A little math to back up my claim.

At 30MPG I would have burned 5,666 gallons. At 45 MPG I burned 3,777 gallons. I saved 1,888 gallons over 10 years. I would have broken even if gas averaged about $1.10/gallon. It didn't. I figured this out when I bought the car except for the other maintenance part. The savings on water pumps, belts, transmission, starters, alternators, and all the general stuff that breaks on regular cars is a bonus.
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jackssmirkingrevenge
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Fri Jul 12, 2013 12:42 am

That's all very well, but what about the moral cost of being seen driving a Prius?

Image

This is the only electric vehicle I could accept in my life:

[youtube][/youtube]
hectmarr wrote:You have to make many weapons, because this field is long and short life
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POLAND_SPUD
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Fri Jul 12, 2013 4:31 am

[youtube][/youtube]
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Technician1002
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Fri Jul 12, 2013 7:31 pm

Unfortunately, I would have serious range anxiety with my commute to drive an electric only.

The hidden truth on electric only is the battery life. The hybrid gets about 10 years or 150K miles only because the state of charge is highly contained within a narrow range. A battery that is regularly fully charged and then deep discharged rarely sees a long service life. Look at phone and laptop battery life for prime examples. There are very few with full battery capacity and over 5 years old.

To make a longer commute possible a larger battery is required. This makes the replacements more frequent and more costly. I would consider an electric as a neighborhood electric vehicle, AKA street legal golf cart for use on short trips, not the freeway.

The battery is supposed to arrive today. I have safely removed the old pack and stripped out the service plug wiring, the ECU, the contractors, etc in prep for the new pack arrival. The expected terminal corrosion is very minimal. The service bulletin/recall for this problem seems to have been effective. I can see remnants of the sealant as I take terminals off.

I hope the new pack arrives soon.
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Fri Jul 12, 2013 7:46 pm

Didnt want to start a thread over this but I built a cannon using a dust collector valve nd I understand dead space nd all the stuff but I wanted to connect a small hose after my ball valve which is my trigger now, want to move it so its more convient to hold nd more fun firing, ,, will this affect my performance nd have any negative results?
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Fri Jul 12, 2013 9:50 pm

jsefcik wrote:Didnt want to start a thread over this but I built a cannon using a dust collector valve nd I understand dead space nd all the stuff but I wanted to connect a small hose after my ball valve which is my trigger now, want to move it so its more convient to hold nd more fun firing, ,, will this affect my performance nd have any negative results?
Exactly the moment when you should start a thread over this. Check out the topic. "Non-Spudgun Related Discussion" :D

Back on topic...

I'd much rather have a well-made diesel than an electric vehicle. I have what's called a "mild hybrid" (eAssist in the GM world) and it's nice to idle without using gas, but hey. I really need a truck again, I wish I hadn't gotten a sedan.
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POLAND_SPUD
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Sat Jul 13, 2013 5:47 am

Unfortunately, I would have serious range anxiety with my commute to drive an electric only.
Fuel cells seem to be the way to go. We wouldn't even have to change much infrastructure - just replace petrol with methanol
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Sat Jul 13, 2013 6:07 am

POLAND_SPUD wrote:We wouldn't even have to change much infrastructure - just replace petrol with methanol
You still need energy to synthesize methanol, so solar/wind/hydro/geothermal energy to do so is still required for a true green vehicle.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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POLAND_SPUD
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Sat Jul 13, 2013 9:11 am

You still need energy to synthesize methanol, so solar/wind/hydro/geothermal energy to do so is still required for a true green vehicle.
The same applies for electric vehicles that use batteries

What's so cool about fuel cells is energy density and the fact that infrastructure for liquid fuels is already in place (gas station etc.). This isn't limited only to powering vehicles though ->> http://en.wikipedia.org/wiki/Methanol_economy
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Sat Jul 13, 2013 1:18 pm

Eeeeenteresting. We go through thousands of litres of the stuff every week at work, best way to clean a reactor when you heat it to reflux :)
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Sat Jul 13, 2013 3:01 pm

LiFePO4 batteries are actually pretty good about cycles. The ones we use on our solar car are rated to 2000 cycles with, I beleive, 90%+ capacity remaining. That's about 3 years at 1 full discharge per year, which you will not see on average days. The cells were about $600/KWH, and peak output of about $107/kW. Weigh about 125WH/kg.

The biggest issue I see with them is charging, although ours are rated for 1C charge rate, meaning they can be fully charged in 1 hour. There exist LiFePO4 cells that can take up to 15C charge, meaning you could charge in 4 minutes. They are heavier and more expensive per kWH ($4343/kWH), but cheaper per KW peak ($48/kW). That hobby pack is also presumably very marked up.

I wonder of a heterogeneous battery could be made to work for less cost (high discharge for peak/accelerating/regen and high capacity for range)
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Sat Jul 13, 2013 3:12 pm

ramses wrote:I wonder of a heterogeneous battery could be made to work for less cost (high discharge for peak/accelerating/regen and high capacity for range)
Better than a homo battery :D
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Technician1002
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Sat Jul 13, 2013 3:36 pm

They are heavier and more expensive per kWH ($4343/kWH), but cheaper per KW peak ($48/kW). That hobby pack is also presumably very marked up.
A typical electric car cruising uses about 15-30KW, so an hour commute would use 15-30 KWH. Add another 2KW if you use the heater or AC.

Cells are about $600/KWH of capacity. You do not want to run them flat and possibly walk the last mile home on a regular basis, so plan on more capacity than your trip will typically require.

To charge a 60KWH pack in 1 hour would require just over 60KW of power draw. Most homes do not have that much capacity. A typical 15 amp outlet on a 20 amp breaker is only good for about 1.8KW.
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ramses
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Sat Jul 13, 2013 10:49 pm

Technician1002 wrote:
They are heavier and more expensive per kWH ($4343/kWH), but cheaper per KW peak ($48/kW). That hobby pack is also presumably very marked up.
A typical electric car cruising uses about 15-30KW, so an hour commute would use 15-30 KWH. Add another 2KW if you use the heater or AC.

Cells are about $600/KWH of capacity. You do not want to run them flat and possibly walk the last mile home on a regular basis, so plan on more capacity than your trip will typically require.

To charge a 60KWH pack in 1 hour would require just over 60KW of power draw. Most homes do not have that much capacity. A typical 15 amp outlet on a 20 amp breaker is only good for about 1.8KW.
I am aware that homes do not have that much capacity (although, no one says you have to charge off of a single 120v 20A breaker). I was pointing to the possibility of a 'fast charge gas station' much like what Tesla is currently rolling out.

As to the power consumption, I foresee that most commutes spend a good amount of time stopped in traffic, using zero power (except for parasitic electrical systems). Even if you cruise at 45 mph for an hour to and from work every day, at 40 mpg, you would spend $7875 on gas at $3.50/gallon over the 2000 cycle life of the pack. That pack would cost $36k, so it wouldn't be worth it unless batteries became drastically cheaper or gas became drastically more expensive.

There is also a lot that can be done aerodynamically to use less power. Our solar car pulls 1.2kw cruising at 45 mph. Granted, it's a 500 lb single seat car with zero storage, but I feel like we can do slightly better even with a more practical vehicle.
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Technician1002
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Sat Jul 13, 2013 11:54 pm

That solar car will need to be able to pass all safety tests, and have enough power to keep up in city and highway traffic. At 1.2KW, it uses less power than my hair dryer. I doubt it could make my 30 mile commute in under 4 hours due to a 600 foot hill and plenty of stop and go traffic lights.

What is your Horsepower to Weight ratio and acceleration?

On most commutes, most people use the AC, Heater, Or defroster depending on weather. Rarely is the weather ideal for a commute most of the year. Many air handlers in cars use up to 200 Watts. Heat or cooling is extra. This is much more than parasitic electrical systems such as power management and instrumentation.
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