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Reviving dead lead acid batteries


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Wheels, $ 5 to $10 per fill according to this:  link for a NZ fill.  

 

You can't really compare a Tesla US 70k to a 35k car.  Just not the same vehicle.  I drove one for 4 days in the US last week, Model S P85D and in insane mode it's awesomely quick.  I think this model is around 130k US.  They are quicker than most sports cars.  

 

This shows just how quick it is: https://www.youtube.com/watch?v=9cA1doO_9h8

 

Like it or not they are coming and will continue to get better and drive battery technology.  The only problem being the current price of oil!  

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Maybe, but I like to see the costs. Here is a brief, (very) rough calc.

 

The car will not be electrically 100 % efficient, and will require quite a few Kwhrs for normal use. I wonder haw many cents per Kwhr they are charged there? The NZ average is about 27-30c per Kwhr from my brief check for north auckland. So;

 

Say your car is 80 percent charge efficient, and has a  120Kw engine. You drive at 1/2 throttle on average, at an average of 70 Km/hr. If you do the Km's that we do, say 2000 per month - that's say 29 hours per month.  At 1/2 output that's 29x 60 Kw, or 1740 Kwhrs.

 

Now, take the 1740 Kwhrs, x 1.2 for charge efficiency = 2088 Kwhrs, at $0.27 = $563.76 per month.

 

Not a lot of difference as far as I can see. What have I C*$%ed up? Anyone got better figures?

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You can't really compare a Tesla US 70k to a 35k car.

Sorry, not what I was meaning. I likely confused the story. Electric Cars range in price dramatically, as you stated with the Tesla at US$130K. I was not referring to the Tesla exactly, just using the $70K as a low figure re electric. A $35K car in the US buys you a very good car. in fact not bad even here in NZ now. But even the next Tesla at US$30K is going to be out of reach for many Kiwis if it was sold here in NZ.

 

IT, I think the numbers look OK. Another angle is the distance one can travel between a charge. Tesla seems to be the leader and their current model is capable of 320K before a 20min recharge. I assume that will be 320K on a flat road. That means for me for argument, it would be unlikely I could reach CHCH on a charge. For my Car, I can get 700Km from a tank and that is a V8. Sure, around town driving is a different story and for a great deal of the population, a Charge will be fine.

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Say your car is 80 percent charge efficient, and has a  120Kw engine. You drive at 1/2 throttle on average, at an average of 70 Km/hr. If you do the Km's that we do, say 2000 per month - that's say 29 hours per month.  At 1/2 output that's 29x 60 Kw, or 1740 Kwhrs.

 

. What have I C*$%ed up? Anyone got better figures?

 

Assuming 1/2 throttle. That would be saying a 60kw car of equal weight and aerodynamics would be driven at 100% load...

 

I believe that around 10Kw is sufficient to maintain velocity for most cars. Factor in an additional 2Kw for aircon etc, and your at 12Kw. Or, at $.28/KwH around $3.40 hour. But thats not allowing for acceleration. How effective is the braking power regeneration? I have no idea, but that helps the acceleration side become less costly, but if you operated at 50% throttle for 10% of the operation you could say that your adding another 6Kwh to the mix - or your running up toward $5.1.

 

Now - more complication to add to the mix. What is the charging efficiency? 80%? ( educated guess at best ) your up to $6.37 per hour - and living rurally we very rarely see an average speed of more than 65Kmh, so your getting close to 10c/km driven. 

 

Want more complication? What current power supply do you need to your house to enable you to charge the car at a reasonable speed alongside all your other electrical demand? Do you end up paying a higher daily line charge? I know that here to go to more than 60A you go from around $1.50 to $22 per day ( and are pushed to having 3 phase, want it or not - yes, you read correctly it goes up around 1500% ).

Factor in the fact that you plug the car in when you get home in the winter, go inside turn on the heating ( 15 - 30 amps ) stove and oven ( 15 - 45 amps ) then hop in the shower and the hot water cylinder turns on ( 10 amps ) and opps - your over 60a on your supply.  Sure, you can set up current management but that adds to the initial investment.

 

Lets complicate this more huh? Range limits you severely. I have driven from Hamilton to Christchurch in one day, towing a trailer with a jet sprinter and spares on it. Say 1200Kg. And 5 of us in the vehicle. Try that with electric power. Any towing will slaughter electric power. Hybrids - thats another story, but you have 2 sets of things to go wrong then.

 

Electric power will be the main form of transport propulsion oneday. I agree its inevitable, specially where we have a very green power source such as NZ has. Charging is going to be a major challenge to overcome. I see that Inductive charging in the roads ( State highways, etc, not all roads ) so you get power as you drive might be a great concept. Who knows - but the technology is far from ready. As the many issues Tesla and others face. Anyone buying the current EV's are paying a very high early adopters penalty.

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There is a calculator you can use on tesla's own web page down the bottom of the page https://www.teslamotors.com/models-charging#/calculator

 

I don't think electric cars are going to be aimed right now at every kiwi, only those who see the value in them and those who can afford the capital purchase price.  In the US especially California there are large rebate schemes to push the sales of electric cars which don't exist here I think, could be wrong I guess.  If you think more a long the lines of pollution reduction and other benefits such as safety, self drive radar etc etc it's a no brainer.  

 

It wasn't long ago that Kiwis and Aussies still thought the commodore was the best car out there and everything else was junk, and look what's happened to them now.  Early adopters pay the price for sure but there are some people who will do it including myself.  My next cayenne will be a hybrid.  

 

Towing is another story for now, sure the old Ford Ranger will have to be kept in service instead of an electric car for that. After driving one last week there are just so many advantages such as lack of engine noise, user interface and the driver radar really works so well on the highway's that I didn't touch the wheel for an hour at a time.  The charging stations work quite well although there don't seem to be enough of them.  Twice we had to wait to charge because all the stations were full but to be honest we were in no rush to a coffee and off we went.  

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I believe that around 10Kw is sufficient to maintain velocity for most cars.

No, if you think about it, the faster you go, the more fuel used and fuel use is related to power.

The better way to work it out is simple. How much energy in Kw does the Battery system hold at full charge. KwHrs are KwHrs. A Kwhr costs (as IT has found) 27-30cents. Times the 27cents by the number of KwHrs you put into the battery, add a little more for loss from the electronics.

 

I don't think electric cars are going to be aimed right now at every kiwi, only those who see the value in them and those who can afford the capital purchase price.

Which is kind of what I was trying to say, rather broadly, in relation to BP's post. That for here in NZ, it is difficult to make it stack up. And as you say SM, in the quoted part above, that if you factor in capital price, then it really is hard to justify the idea if the idea is one of saving. Remember that the idea behind the electric vehicle is to reduce emissions and the only way emissions will be reduced is for the cars to be available to the masses. As you said earlier, it is coming. Yes it certainly will. All aspects will improve. But currently it is far from it. And the true costs are hidden when you have the rebates and subsidies and freebies etc etc. But then, they need the volume on the road to make more charging sites available. So the subsidies can be considered as building the infrastructure. But all summed up, buying one right now because you think you are saving the Planet is just fooling ones self.

     By the way, there are now heavy transport trucks operating in Europe that are fully electric.

      

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An interesting conversation...

First to the fast charge necessity..I dont use my engine as a battery charger. My solar panels and wind generator keep pace with my needs in all but exceptional circumstances. 

If I needed more power I would add more panels and more batteries followed by a small diesel generator as a last resort.

Fast deep charge by virtue means less battery life.

Ultimately it depends on how much power you use. Now I am a live aboard and have been for many years....even though I live in a marina, my only power needs above what I produce is for an occasional heater. ....and i dont live like a monk in a cave....(you should see the size of my sound system amp : )

 

As to the electric car question..it is interesting that the financial side is being finessed in the interests of an accurate appraisal ...but that other cost difference...the true cost in dollars of a petrol/oil based stream..and its on going damage is not costed in as the bench mark.

It is as though the two are starting on an equal standing environmentally ....and then costs discussed .

I would suggest that as the number of vehicles on this planet increases we will indeed be a bit more realistic in our financial appraisals..

The "altruistic do goody greenies" of today will be classed as the sensible early adopters of tmmrw.

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Indeed it is an interesting discussion.
"Level playing field", yeah well you see, there in lies a problem and what I am really trying to say. How much of the field is level and is the same sport being played on each side of the field. It's not about the "greeny" thing. I get tired of this "us poor greenies, but one day we will be proven right" attitude. Ones like myself are arguing that when it comes to what we think is "green technology", in fact the real effect on the environment is being hidden. As I said in my first post on this subject, the battery itself, that very heart of "green", is in fact a very carbon unit hungry device i both it's creation and in it's destruction. I have no way of knowing how to calculate what that Carbon unit would be and then divided over it's life. I would hope it was still better than Hydrocarbon energy. But then when you add in that some countries produce electricity by burning Oil, Coal and Gas anyway, is the battery any better? I don't know, I am trying to shine a light on the fact. Because it is very easy to put blinkers on and say I am doing my bit for a better planet, when all that has happened is, one has shifted the bad stuff being down from ones backyard to someone else's back yard.

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Wheels, the 10Kw figure was an average figure that apparently covers most EV cars. I am trying to find the website which had lots of tests on various EV's and included the average power consumption requirement for mixed driving. Little super minis such as the Mitsi i-MiEv may do better ( although going by Mitsubishis own literature their 16KwH battery will do 100Km in the combined test which points directly at 10Kw to maintain the average speed of 65-70kmh.  The average of course included all speeds from 0 through to, I assume, 100kmh.

 

Maybe the 10kw figure for average power requirements is a little light.

 

What this does not include are the fuel savings when stationary vrs an internal combustion engine which does not have a stop/start system to turn it off when stationary.

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That Telsa calc shows 13.5 KWhrs for a 40 mile (64 KM) drive. But I'd also expect that is on the flat, start - drive - stop, no traffic, best possible, like the quoted fuel costs from most manufacturers.

 

If that was correct, then it works out about $10.00 cheaper per week than the Admiral spends getting to work and back in her Suzuki Swift - The Jap Electronic one with Idle Stop, regeneration for Lithium batt used for restarts etc etc - it's the Swift that Suzuki used for economy competitions, not the std NZ one. Averages about 4.7 ltrs per 100 Km, in REAL Auckland driving, at rush hours, which is pretty remarkable for a petrol car, IMO.

 

Oh yeah TT, the Suzuki is 62Kw. I used the 120 Kw figure before, as it is 1/2 way between our two cars, just an arbitrary number. 10kw for constant speed, I agree, but that is not realistic driving, as you have alluded to above.

 

And IB, yep I was just thinking of the costs quoted, not the effect on the Planet. If I could afford a Tesla, I'd have one now. They are cool. BUT there is still the effect of the disposal of the electric cars at end of life - they produce some pretty toxic waste at this time. That also has to be considered - it is my understanding that the least environmental footprint of any car currently available is a small turbo diesel...

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I totally agree with "cradle to grave" analyses. 

Advertising the good bits and ignoring the bad, should stay on breakfast cereal packets !

Another question is if the production of lithium can be scaled up to meet demand. (and also how large are the long term easily accessed reserves).

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Anyhow, back to my original query, 

 

I finally got down to the boat today, started the engine, turned the emergency cross over on for about 5 mins, then turned it off and taadaa, the house alternator and next step reg started delivery current to the house bank, so thats sorted and thanks everyone for the tip, albeit that I'm a little embarrassed i didn't think of it!

 

I could only run the engine for a 15 mins, hence the battery was still sitting below 8 volt once i shut everything down and left, but hopefully a run for a few hours this weekend will spark the bank back into life, but by how much is the question. 

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Yes what IT said. Soft plate Sulphation starts as soon as a 12V FLA battery drops below 12.5V and the rate of sulphation increases as the voltage drops. Soft plate Sulphation is the only form of Lead Sulphate that can be restored back to normal plate chemistry with proper charging, within hrs of the discharge. If the battery remains in a low state of charge for too long, or if the Electrolyte drops too low and exposes the plates to air, the Sulphate changes to a hard material that can not be changed back, no matter what you do. Hence why I laugh at the claims of these silly reverse pulse chargers that are supposed to get rid of sulphation and rejuvenate the battery. By the way, just try and reverse charge a battery, even for a millisecond and see what result you get. No actually don't. It wont go well.
So in short, get em fully charged as soon as you possibly can and you will need 4 or 5 hrs, so go for a good motor somewhere.

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