Power consumption for balancing the battery ??

[wmcbrine]

(This belongs in a different thread -- )

I would like to know exactly how many kWh it will use to go from no charge to full charge on the included 120VAC small charger.

The battery is 16kWh, but there's some inefficiency in charging, especially at Level 1 (i.e. 120V). The manual, which I think is pretty close to right, says that it takes about 22 hours. The included charger does 8A @ 120V = 960W, * 22 hrs = ~21kWh. You can improve on this by getting a different/modified charger that does up to 12A on a 120V circuit.

 

[JoeS]

Hello: I just joined because I am inching closer to purchase of a 2012 i-MiEV with 17K miles on it. I would like to know exactly how many kWh it will use to go from no charge to full charge on the included 120VAC small charger. I have a Kill-A-Watt device that will show accumulated draw over a specified time; has anyone use one of those to determine this? I am assuming the car would pull more current at the beginning then taper off toward the end of the charging period; just trying to quantify that. I realize the charge time is long for this included device but I cannot afford to add fast 240VAC charger to my house right now.

thomash85715, welcome to the forum.Yes, a bit off-topic, but if you look at the graph on this post your question might answered: http://myimiev.com/forum/viewtopic.php?f=28&t=3697&start=10#p31704
If you'd like to continue this discussion start a new thread and we'll be happy to answer your various questions and I'll move these few posts over there.

Much more significantly, your question is unrealistic in real life, because we never ever let the battery go to zero and always randomly opportunity-charge. Basically, what you will find is that if you plug in the car in the evening you will have a 'full tank' in the morning. Many of us L1 (120vac) charged for years with little need for L2 (240vac) charging. If you would like to describe your typical daily driving car usage scenario we'll be happy to comment. Incidentally, in your climate and in the interest of battery longevity, you normally do not want to fully charge the car and only fully charge it just before setting off on a longer trip.

Also, exactly how is the battery warranty transferred to a subsequent owner? Is there a transfer fee or registration procedure or does mitsubishi track it via VIN?

Yes, Mitsu tracks it by VIN. When you buy the used car you can simply go to the Mitsubishi website and register yourself.

 

[Don]

I am assuming the car would pull more current at the beginning then taper off toward the end of the charging period; just trying to quantify that. I realize the charge time is long for this included device but I cannot afford to add fast 240VAC charger to my house right now.

At the risk of drifting this even farther off topic - :shock:

The supplied OEM EVSE is limited to 8 amps @ 120 volts which is 960 watts. With a 360 volt pack, 960 watts is only 2.66 amps going into the battery, give or take. No matter how you measure that, it's little more than a 'trickle charge' so there's no tapering going on until the cells are completely full and cell balancing begins

A 'normal charge rate' for lithiums is considered to be 1C, or one times the capacity of the cell, which for our cells is about 50 amps. You can charge them faster (not with the charger built into the car however) and some EV's do, but 1C is considered a standard of sorts for lithiums - Fast, but not fast enough to harm the battery. So our 8 amp EVSE which is putting 2.66 amps into the pack is about 1/18th of a 'normal charge rate' - Slow as a snail, in other words :lol:

If installing a dedicated 240 volt outlet in your garage is impractical at this time, consider sending your OEM EVSE in to the guys at http://www.evseupgrade.com and they will update it so it will charge at 12 amps on L1 (120 volts) instead of the 8 amps it came with, *and* that same (modified) OEM EVSE will also do 13 amps using 240 volts (L2). The charge time on120 will be reduced by 1/3rd (12 amps vs the 8 it came with) *and* if you decide in the future you might need even faster recharges, you could fabricate an extension cord which plugs into your household dryer outlet and your modified EVSE will recharge the car in 5 hours or less, depending on how low it is when you start the charge. Many of us here have the Upgraded EVSE's and use them daily - It's the biggest bang for the buck you will find to get faster recharges

Don

 

[thomash85715]

Sorry to be off-topic. Did not want to start a new thread when it appeared this one was related to my query. The links to previous discussions and data is enlightening. Thank you for helping me understand what I might be getting into here and what to expect.

 

[Don]

Where these topics 'drift' to doesn't bother me in the slightest . . . . but not everyone here agrees with me

IMO, your questions are close enough to what was being discussed to warrant inclusion - Sorry if I made you feel otherwise

Don

 

[thomash85715]

No one made me feel bad at all...everyone here is great. Here in my town the overall cost of my electricity is 13.5 cents per kwh. Using the figures JoeS compiled, it would cost 3.2 cents of electricity to go each mile in a i-MiEV. In the 82 BMW 320 I use for urban errands, it costs me 9.6 cents of gasoline to go that same mile. True, the much higher efficiency of the i-MiEV is somewhat offset by the higher cost of an electric kilowatt hour versus a carbon fuel kilowatt hour. I used 33.7 kwh per gallon of gasoline as my reference. Calculating the elimination of worry over oil changes, coolant leaks, faulty O2 sensors, clogged injectors--OK I need not preach to the choir--might be harder to pinpoint but the Mr Spock in me finds the logic of making this switch unassailable.
As time goes on, will the cost of gasoline rise faster than the cost of electricity? I think yes. If I give in and lease a solar system for my rooftop, the i-MiEV advantage will grow even more. Is there a thread for listing all the intangibles for convincing me to take the plunge?
Thank you.

 

[Don]

My 'rough numbers' are as follows. If you have a car which has an around town mileage rating of 20 mpg and you're buying $2 gas, or if your car gets 25 around town and you're buying $2.50 gas (or most anywhere in between) you're spending about 10 cents a mile on gas. A $30 oil & filter change every 3,000 miles adds another penny per mile and a $600 timing belt at 60K plus the other incidentals (air filters, O2 sensors . . . . the whole gamut of other odds and ends you spend keeping an ICE going) adds at least another 1.5 cents per mile, so the 'average' around town (these are 'around town' cars for the most part . . . . at least that's what they're really good at) costs for an 'average' ICE is about 12.5 cents per mile - A bit less if the iMiEV would be replacing an econo-box, lots more if it's replacing a pick-up or a big car, but for the sake of this argument, it's roughly 12.5 cents per mile

My electricity is 11 cents per kwh and on average I use about 2.5 cents per mile - A bit more if you're using the inefficient OEM heater, but we seldom do that, so for a 'rough argument' 2.5 cents per mile vs 12.5 cents per mile, or a savings of 10 cents for every mile driven. 10 cents per mile for 100,000 miles is $10K - We paid $8,700 for our second iMiEV with 3,900 miles on it so if I drive it 85,000 or 90,000 miles before I 'toss it' then it paid for itself . . . . but it will still be worth *something* even after 100K - I'll put whatever batteries survive into something else just to play around with

Adjust any of the numbers to suit your own situation and you may get a bit more or less, but for anyone considering buying a used 2012 to do 90% of their around town miles, it's basically a 'free car' no matter how you look at it. The fact that it's fun to drive, virtually silent, virtually maintenance free, the easiest car to get into and out of that I've ever owned (important for all those ins and outs when running errands around town) makes it the most practical solution for doing what it was designed for - Toting 2 to 4 people and cargo around town in relative comfort for the least number of pennies per mile of anything you could buy

You could further bolster the argument by factoring in the fact that your BMW is going to last you much, much longer - Stop and go around town miles are the worst kind of miles for an ICE. If you trade your BMW every 4 or 6 years, you'll get lots more for it because it will nave many fewer miles on it that it would if it was your daily around town driver. Most any way you look at it, not buying a used iMiEV to do the majority of your around town miles probably isn't a smart financial decision . . . . if that matters

Don

 

[Phximiev]

We computed our break even at the time of purchase at no more than four years. Less if you factor in the probable cost of repairs. We spent $4,500 in repairs on our Grand Caravan all related to the engine and more was visible on the horizon. We were spending $300.00 to $350.00 a month on gas.

It was a no brainer to buy the 'Miev.

Since we sold the GC, we have done all of our in town driving with the 'Miev and when we need another car we borrow or rent, see the Car Sharing topic.

 

[thomash85715]

So glad to hear the choir in full voice and I am joining in. Wisdom of the initial switch is obvious but... the people whispering in other ear are trying to scare me with the big battery fail scenario. Yes a 2012 used i-MiEV still has warranty left but what if, what if, what if everyone asks. If the batteries fail soon after the 8 year period is up in 2020, what oh what would I do? I offer that no one can predict the future, the cost then of replacement is likely to be lower than it is right now, and please I hope there is more to offer on this as it does concern me.

 

[PV1]

What if? Then you got a good 8 years out of a wonderful car, and then you can step into a new EV with 400 miles of range :mrgreen: , unless there is a decent battery rebuild option available.

Also, if you check, that 8 year warranty might've been upgraded to a 10-year warranty (many of our cars were).

 

[blackheart]

So glad to hear the choir in full voice and I am joining in. Wisdom of the initial switch is obvious but... the people whispering in other ear are trying to scare me with the big battery fail scenario. Yes a 2012 used i-MiEV still has warranty left but what if, what if, what if everyone asks. If the batteries fail soon after the 8 year period is up in 2020, what oh what would I do? I offer that no one can predict the future, the cost then of replacement is likely to be lower than it is right now, and please I hope there is more to offer on this as it does concern me.

thomash85715 - I bought my car banking that there would be a better replacement solution when my battery finally gives up the ghost. EVWest is a company down in CA that are doing EV conversions of classic cars. They don't do a conversion unless they can get 200+ miiles out of it. So, I am hoping, that there will be someone who will be able to replace my battery with a lighter, more power dense, longer range battery in a few years - complete with a new charger that is bigger than what I have - and all integrated into the OEM BMS. (fingers crossed!!!)
Until then, I'm still loving my little city car!!