I have seen several coments in other posts about battery fans and battery temperature management on the I-MiEV. It's not clear in the sales literature or listening to videos from Mitsubishi engineers but I-MiEV's do not have any traction battery fan unless you have one of the two options---either the battery warming system or the quick charge port. The fan isn't used for any battery temperature management except in very cold temperatures (warming system or quick charge option) or during quick charge (cooling via A/C operation). If you have either option, you will hear the fan start for a few seconds each time you plug in the EVSE. This is to clear the filter on the top of the battery pack. There is no temperature management during normal operation of any I-MiEV. These two optional systems only operate when the battery is being charged, not when driving. I-MiEV's without these options have no place for air to enter the pack and no ductwork inside the pack to distribute any air. There is a small vent on top of the pack but other then that, the pack is sealed. The pack is at the mercy of the outside temperatures just like a LEAF. Mitsubishi really missed the boat on this one as all the component parts are there to make a decent TMS but they never did it.
Battery temperature management
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Are you basing this on the fact that you can hear a fan when you plug in a ChaDeMo equipped car and you can't when you plug in an 'ordinary car'? . . . . or do you have some documentation which says the rest of the cars do not have an air cooled battery? If so, give us a link or two please
All the literature for the 'standard' car (without ChaDeMo or the cold weather package) that I have seen advertise that they all have air cooled battery packs
A BETTER BATTERY BY DESIGN
For over 40 years, Mitsubishi has been leading the charge in electric vehicle innovation, and the i-MiEV is the culmination of all their pioneering work. The custom made Lithium-ion battery packs are safely mounted to the RISE-chassis body, feature two cooling systems and are warrantied for 8 years or 100,000 miles. The time for a better electric car battery is now, and you can find it under the i-MiEV.
This advertisement says that only the ChaDeMo equipped cars have A/C ducted through the battery (one system) but it sure sounds like EVERY car has the other system where a fan which pulls air through the battery
TWO LITHIUM-ION COOLING SYSTEMS
The custom-made battery pack on the ES trim of the i-MiEV features a fan-driven, forced-air induction system that automatically engages to protect the battery from overheating during charging. Drivers can upgrade to the Premium Package, which also gives drivers the ability to charge the i-MiEV using public quick-chargers. Because quick-chargers can tend to heat batteries and reduce their efficiency in the long term, we've added an air-cooling system that draws cold air from the air conditioning unit to keep the battery nice and cool, even in hot climates.
And another mention of the cooling system
OUR EV BATTERY IS ALL MITSUBISHI
While some electric vehicles adapt third-party battery technology, ours is Mitsubishi all the way. To ensure world-class performance, we initiated a joint venture called Lithium Energy Japan to engineer a high-performance lithium-ion electric car battery specifically for the i-MiEV. The result is our custom 16 kWh battery pack that delivers everything you need: a long air-cooled life, responsive power, fast charging and great range. Thanks to our advanced electric car technology, we can back our battery with an 8-year/100,000-mile limited warranty.
Even Wickipedia says it's air cooled . . . . and Air Conditioned *if* you have the ChaDeMo
BATTERY
The 16-kilowatt-hour (58 MJ) lithium-ion battery pack consists of 88 cells placed under the base floor. The pack has 22 cell modules connected in series at a nominal voltage of 330 V. There are two 4-cell modules placed vertically at the center of the pack and ten 8-cell modules placed horizontally. Developed by Mitsubishi and GS Yuasa for both high specific energy and high rate discharge and manufactured by Lithium Energy Japan, a joint venture of GS Yuasa Corporation, Mitsubishi Corporation and Mitsubishi Motors Corporation. The entire pack has a specific energy of 80 Wh/kg. The battery has a forced air cooling system to prevent overheating during high charge and discharge rates and consequent damage. There is an integral fan in the battery pack. For rapid charging, the battery pack is additionally cooled with refrigerated air from the cars air conditioning system.
Don
All the literature for the 'standard' car (without ChaDeMo or the cold weather package) that I have seen advertise that they all have air cooled battery packs
A BETTER BATTERY BY DESIGN
For over 40 years, Mitsubishi has been leading the charge in electric vehicle innovation, and the i-MiEV is the culmination of all their pioneering work. The custom made Lithium-ion battery packs are safely mounted to the RISE-chassis body, feature two cooling systems and are warrantied for 8 years or 100,000 miles. The time for a better electric car battery is now, and you can find it under the i-MiEV.
This advertisement says that only the ChaDeMo equipped cars have A/C ducted through the battery (one system) but it sure sounds like EVERY car has the other system where a fan which pulls air through the battery
TWO LITHIUM-ION COOLING SYSTEMS
The custom-made battery pack on the ES trim of the i-MiEV features a fan-driven, forced-air induction system that automatically engages to protect the battery from overheating during charging. Drivers can upgrade to the Premium Package, which also gives drivers the ability to charge the i-MiEV using public quick-chargers. Because quick-chargers can tend to heat batteries and reduce their efficiency in the long term, we've added an air-cooling system that draws cold air from the air conditioning unit to keep the battery nice and cool, even in hot climates.
And another mention of the cooling system
OUR EV BATTERY IS ALL MITSUBISHI
While some electric vehicles adapt third-party battery technology, ours is Mitsubishi all the way. To ensure world-class performance, we initiated a joint venture called Lithium Energy Japan to engineer a high-performance lithium-ion electric car battery specifically for the i-MiEV. The result is our custom 16 kWh battery pack that delivers everything you need: a long air-cooled life, responsive power, fast charging and great range. Thanks to our advanced electric car technology, we can back our battery with an 8-year/100,000-mile limited warranty.
Even Wickipedia says it's air cooled . . . . and Air Conditioned *if* you have the ChaDeMo
BATTERY
The 16-kilowatt-hour (58 MJ) lithium-ion battery pack consists of 88 cells placed under the base floor. The pack has 22 cell modules connected in series at a nominal voltage of 330 V. There are two 4-cell modules placed vertically at the center of the pack and ten 8-cell modules placed horizontally. Developed by Mitsubishi and GS Yuasa for both high specific energy and high rate discharge and manufactured by Lithium Energy Japan, a joint venture of GS Yuasa Corporation, Mitsubishi Corporation and Mitsubishi Motors Corporation. The entire pack has a specific energy of 80 Wh/kg. The battery has a forced air cooling system to prevent overheating during high charge and discharge rates and consequent damage. There is an integral fan in the battery pack. For rapid charging, the battery pack is additionally cooled with refrigerated air from the cars air conditioning system.
Don
None of that is correct. It applies only if you have the optional quick charge port or warming system and as I mentioned it is only active under certain conditions when charging. I have two I-MiEV's---one with the battery warming system, the other without. Both are SE's. If you take the motor room cover off and look at the top rear of the battery pack you will see the fan connector and wire on the car with the warming system. The other car has only a rubber plug to fill the hole where the wire would go----no fan. Looking at the center console on the drivers side where the heater duct exits, you will see a actuator mounted on the duct to divert air into the pack on the car with the warming system. There is no such duct on the other car or the actuator. Looking under the car with a flashlight, you can see where the duct from the heater connects to the battery pack through a rubber connector. There is no such connector on the car without the warming system. As I said before, if you have a car without those options there is no airflow in or around the battery. If you want to dig deeper, go to your dealership and look at the salesmans training information for the I-MiEV--it spells it out quite clearly. In addition I have the service manuals and the technical information manual for the I-MiEV which also lays out what is in the car and what is not. The optional systems are the same in design with the warming system turning the heater on prior to charging in -4F temperatures and directing heated air into the pack to raise the temperature before starting the charge. If you have the QC port, in addition to the warming function, the system can be used to use the car's A/C system to cool the battery if the temperature exceeds 86F during the charge. The system never operates except in those to modes---in fact it cannot. Even when you hear the fan running for a few seconds when you plug in the EVSE there is limited airflow to the pack as the damper door by the heater is sealed. It only opens when requested during warming or QC cooling.
I was really unhappy with this as I live in a warm climate. I leased the original I-MiEV and when I found it had a cooling system (that could be easily modified to make it work all the time) I tried to buy out the lease. However, the residual was stupid money so I bought a second car. To my suprise, the other car did not have either option, therefore no fans, ducts, acutators, etc. I went back to the dealer who also thought all I-MiEV's had some kind of airflow system in the battery pack---non of their remaining cars had either option so I was stuck with what I have. What's really stupid about this whole thing is The warming option is only $175.00
I was really unhappy with this as I live in a warm climate. I leased the original I-MiEV and when I found it had a cooling system (that could be easily modified to make it work all the time) I tried to buy out the lease. However, the residual was stupid money so I bought a second car. To my suprise, the other car did not have either option, therefore no fans, ducts, acutators, etc. I went back to the dealer who also thought all I-MiEV's had some kind of airflow system in the battery pack---non of their remaining cars had either option so I was stuck with what I have. What's really stupid about this whole thing is The warming option is only $175.00
Don, after re-reading your reply to my post, I should have said only the parts that allude to all cars having some form of battery temperature control is inaccurate. In fact, even the Nissan LEAF has a "air cooled" battery. The fact that the cooling is by convection into a closed compartment is how it is "cooled" it is still air cooled. A black crowbar laying in the summer sun is air cooled by the heat radiating into the air. It's just something you might not want to pick up without gloves on. Unlike our cars the LEAF at least has a air gap between the individual cells in the modules. In the I-MiEV the cells have no place for airflow around them in except the top, bottom and sides of the four or eight cell modules. Our only hope is that our battery chemistry is a little more tolerant of high temperatures then the LEAF battery. I think we haven't seen a problem with the I-MiEV for a couple of reasons. First the older LEAF's are the ones showing the problems---there's an extra summer on the LEAF's then on the I-MiEV's in our country. Second, there is a smaller sampling of I-MiEV's then LEAF's. Third, the LEAF has a dash display that shows the battery degradation to the driver---There is no such display on the I-MiEV. Many LEAF owners had no idea that there batteries had deteiorated until they lost a bar on the display even though they had lost nearly 20% of the total pack capacity. I would like to hear from any forum members from Phoenix about how their I-MiEV's are doing. Again, I stand by the fact that most I-MiEV's have no cooling of the battery other then convection and no I-MiEV's have way form of controlling battery temperature except when QC'ing (cooling) or pre-charging (heating). The fan etc. will not operate when the car is in the ready mode or being driven.
RobertC
Well-known member
You are bumming me out. You're right, but you are still bumming me out.siai47 said:
I have learned the hard way that the Mitsubishi dealers, including sales people and mechanics, know very little about the i-MiEV. I was told by the dealer that the DC Quick Charge option could be added. Wrong.
I could understand the lack of knowledge at the dealer since the electric vehicle is like nothing they have ever seen, but what really surprises me is the wrong information about the battery cooling on the Mitsubishi website.
But how would you air cool a battery when it is 100 degrees out?
If your i-MiEV is parked in the sun, then the inside temperature of the car is probably over 100 degrees.
You wouldn't want to use that air to try to cool the battery.
You wouldn't want to use the outside 100 degree air to cool the battery either.
The only option would be to run the air conditioner and use the conditioned air.
But how much would you want to run the air conditioner during a six hour charge? Would it turn into a 9 hour charge?
I'm thinking that the i-MiEV's 3.3kW charger does not raise the battery temperature significantly during charging.
However, the DC Quick Charger probably does raise the battery temperature significantly during charging, which is why the air conditioner is used to help cool the battery.
I don't have much faith in the Mitsubishi dealers or Mitsubishi Motors North America, but I still hold out hope for the Mitsubishi engineers.
Even the Tesla Model S, with a liquid cooled battery, does not cool the battery when the vehicle isn't charging.
If you're parked all day in 110 degree heat, then your battery is at 110 degrees all day.
Also, looking at Ben Nelson's videos on YouTube, it does look like there is separation for air flow in the i-MiEV's four and eight cell modules, so that each of the 88 cells has room to dissipate heat.
Finally, is there a way to tell what battery capacity loss there is with the i-MiEV?
Can we tell by hooking up the Mitsubishi MUTIII tester?
I have almost 18,000 miles on my i-MiEV and I am curious to know.
Cooling the battery in cars with the warming or QC option is pretty easy and I would have thought Mitsubishi would have figured it out. In my case with the leased car with the warming system all I did was disconnect the acutator at the floor duct and then move the arm so that the damper door in the duct would always divert air to the battery. When it is hot and you want to cool the battery, you can select where the air from the A/C system goes by turning the lower knob on the HVAC system from "face" to the "face/floor" position. This directs half of the air into the cabin and the other half into the battery. The A/C blower pushes the air through the battery pack and it exhausts though the battery pack fan (which isn't turning nor is it necessary) Using this method I can control the pack temperature while driving. The battery could also be heated in the winter using this same method by selecting "heat" from the HVAC, however usually battery heating is unnecessary and would be counterproductive based on the energy required to provide heat from the hot water heater vs. energy output gained from a warmer battery. The battery has a lot of mass, therefore the rise or fall of the temperature of the cells in the pack takes time. Any cooling you can provide while driving will keep the cell temperatures lower while parked then they would have gotten if you never cooled them in the first place. I put a temperature probe into the pack and using this method, I was able to get the air temperature in the battery enclosure down from over 100 degrees (on a 95 degree day) to below 75 degrees in just a few minutes. Thats not to say the cells themselves were at that temperature but at least they were able to disapate their heat by convection into the cooler air at a higher rate. For those of us who don't have the ductwork in the cars the final blow it that Mitsubishi will not sell you the parts necessary to modify the car to install the parts needed to do this. They do not service any components within or attached to the battery pack. They say (as all cars are still under warranty) they will handle any problems with in the pack and service it only as a single part under warranty. My question was what to do if I have accident damage or if I don't care about voiding my warranty what about selling me parts anyway. The answer was a not to polite NO.
MLucas
Well-known member
siai47 said:
I've read that in the winter, a best practice is to charge your battery before you need it so that the battery is warmed by the charging process versys charging the car when you get home and letting it sit all night cooling down. I'm thinking this goes with the thermal mass of the batteries.
I think you are onto something with this manually moving the door flap into the battery box. Too bad MMC won't sell you the parts but I think it's something you could do with a bit of HomeDepot engineering if like you said you don't care about the warranty. Some PVC plumbing parts is all you need. You may need to drop the pack but that guy that bought the flooded i-MiEV was able to get it down by himself. I have a motorcycle jack I bought from Canadian Tire on special for cheap that has a nice wide base for lifting bikes, if I ever need to drop my pack I plan on using that.
RobertC
Well-known member
Interesting project.siai47 said:
How about using the remote at the start of charging to blow air conditioned air into the battery pack?
When I installed the factory speakers in the rear doors of my ES model, the guy at the parts counter looked up the part number and I ordered the speakers at http://www.ricartparts.com/. You could give it a try. The guy at ricart parts will even email you a drawing of the part that you are ordering to make sure it is the right one. My ES model has the warming option. My VIN # is JA3215H12CU015949 and the parts should come up for this vehicle. I too have the manuals for the i-MiEV. What parts to you need exactly?
It's possible you could use the remote to pre-cool the battery. However, I am not up to speed on the remote, but is seems the remote causes the A/C (or heat) system to default to some pre-configured operation. I don't know if it overrides the positions of the dash controls. As far as parts are concerned, some of the parts can be ordered from the dealer incuding the two ducts that are inside the passenger compartment. After that, nothing that is part of the traction battey pack is available. There are two pieces inside or on the pack that you need. One is the external boot that connects the ductwork to the top cover of the pack. The second item is a internal ductwork piece inside the pack to direct air to the various battery modules. I can see Mitsubishi's point about this as installing this stuff after the fact isn't for the faint of heart. There are also lethal voltages running around inside the pack to contend with. In the case of those with the QC or warming option, just removing the actuator and manually moving the damper lever gets you all the benefits you need for zero expense.
RobertC
Well-known member
I'll check how the remote cools the next time I charge to see if the cold air can be diverted to the battery.siai47 said:
As for the two pieces inside or on the pack, you could make something to take the place of the external boot, and watch Ben Nelson's YouTube video for the ductwork. http://www.youtube.com/watch?v=EmgRuhqba0I You can get a good look at it at 3:48 in the video. I think that you could get effective cooling without it. If you push cold air in one end of the pack, then the hot air will be forced out the other end, and the coldest air will sink to the bottom. You wouldn't need to remove or work in the battery pack.
siai47, I appreciate your posts and and enjoyed your description of the cooling diversion, as well as the jaraczs' photographs of the battery ducting. I also understand your frustration with having purchased a second iMiEV, only to find that it is missing all the battery ducting that your previous leased vehicle had. Your concern is quite evident in your various posts on this subject.
I submit that perhaps our iMiEV situation is less dire than the Nissan Leaf's. So far, the iMiEV seems to me to be a pretty-well-engineered car. Mitsubishi had significantly-more experience with electric cars than Nissan when they placed it on the US market, and I seem to recall reading somewhere that the iMiEV's cell internal resistance is less than the Leaf's (resulting in less internal heat generation under load). Mitsu's concern with batteries seems to be more related to low temperatures than high, perhaps a result of a battery chemistry formulation more favorable to high temperatures than Nissan's(?). The absence of forced-cooling (except for CHAdeMO-equipped cars) reflects this. Since, as was pointed out, the addition of this cooling ducting would have been a minimal cost item for them, I would think that their internal benefit-cost analysis would have erred to the conservative if they thought there might be an issue.
Nothing so far points to an iMiEV capacity-loss that Nissan has experienced with their Leaf in the extremely high temperature southwest US environment - quite frankly, even their situation is quite limited, and the Leaf owners' paranoia over losing some capacity is perhaps a bit overblown, IMO, they having the advantage(?) of vehicle instrumentation that can make them nervous. Reality is, that unless we have a fixed daily commute that pushes the iMiEV's range limits, it's really hard to quantify any capacity loss because of all the other variables that can affect range. Time will tell…
My reason for posting this is to try to allay an possible concerns that non-techies might be having as a result of this discussion. So far, nothing is pointing to any battery issues with our iMiEV, at all.
I submit that perhaps our iMiEV situation is less dire than the Nissan Leaf's. So far, the iMiEV seems to me to be a pretty-well-engineered car. Mitsubishi had significantly-more experience with electric cars than Nissan when they placed it on the US market, and I seem to recall reading somewhere that the iMiEV's cell internal resistance is less than the Leaf's (resulting in less internal heat generation under load). Mitsu's concern with batteries seems to be more related to low temperatures than high, perhaps a result of a battery chemistry formulation more favorable to high temperatures than Nissan's(?). The absence of forced-cooling (except for CHAdeMO-equipped cars) reflects this. Since, as was pointed out, the addition of this cooling ducting would have been a minimal cost item for them, I would think that their internal benefit-cost analysis would have erred to the conservative if they thought there might be an issue.
Nothing so far points to an iMiEV capacity-loss that Nissan has experienced with their Leaf in the extremely high temperature southwest US environment - quite frankly, even their situation is quite limited, and the Leaf owners' paranoia over losing some capacity is perhaps a bit overblown, IMO, they having the advantage(?) of vehicle instrumentation that can make them nervous. Reality is, that unless we have a fixed daily commute that pushes the iMiEV's range limits, it's really hard to quantify any capacity loss because of all the other variables that can affect range. Time will tell…
My reason for posting this is to try to allay an possible concerns that non-techies might be having as a result of this discussion. So far, nothing is pointing to any battery issues with our iMiEV, at all.
Vike
Well-known member
Thanks for that. But though I bought my i-MiEV w/QC, this is still among the more depressing threads I've read in quite a while. Some of us (i.e., moiJoeS said:
) could get pretty snooty at times about Nissan's battery-baking sealed box, contrasted with the clearly better thought-out air cooled/heated Mitsu battery pack. For it to turn out that this was just ignorant marketing hype, extolling the virtues of features that were in reality both less consequential than claimed and less widely available, is as much a black eye for MMNA as it is an embarrassment to those who believed their pap. And not to put too fine a point on it, but . . . now that we know they lied to us about this, one must wonder what ELSE they might have lied about.Given the very misleading marketing materials and poor communications, if these cars do develop heat-related problems (which I dare hope they will not), Mitsubishi may find themselves on the wrong side of a (relatively tiny) class action lawsuit.
This discussion wasn't started to try to alarm anybody about how their I-MiEV will or will not perform in hot weather conditions. I started it after I had read several threads that mentioned the battery cooling system that was thought to be standard equipment on all I-MiEV's. I leased the first I-MiEV with the optional battery warming system and quickly discovered that it could be easily modified to allow cooling (manually controlled) if desired. Everything I had heard about the I-MiEV, had seen in sales literature and found on the internet seemed to point to the fact that at a minimum, there was a battery "fan" in the traction battery enclosure. I live in central Florida and in addition to the leased I-MiEV I had a leased 2012 LEAF which has now been replaced with a 2013. My mistake was to buy an additional I-MiEV and assuming all cars had some sort of cooling system. I was really suprised to find out the truth. I honestly believe that even the dealer thought this was the case. It wasn't until I got a service manual and technical information manual and went over the salesman's books that I found out the truth. Am I dissapointed? A little. Am I mad? No. I have owned several other EV's in my life including a Rav4-EV and a couple of Chevrolet S10-E's. Both had some sort of thermal management system that can be a blessing or a curse. The air-cooled Rav wasn't much of a problem and could be used in a closed garage. The S10's were nigthmares as the active system (Freon refrigerated) would run anytime the vehicle was plugged in even when not charging. It was impossible to park it in a closed garage and not come out later to find the A/C system cranking and the garage well over 110 degrees on a normal summer day. I felt I had found the perfect solution where I could park the I-MiEV in an air conditioned garage and then if the need to keep the pack cool arouse, I could provide cooled air to it. This works well on the leased car which I have been driving. The one I bought had 30 miles on it when I bought it---it now has 90. I am going to adapt something to cool the pack before I start to drive in hot weather. I know the Li-ion batteries (in fact all batteries) are happier at cooler temperatures. If you read Yuasa literature about the LEV-50 (which is the basis of our battery pack) they live a lot longer and produce the most energy at no more then 77 degrees--this is a fact from their own documents. The cycle life and calendar life also improves as you lower the temperature below 77 degrees. I have also found that a temperature above 86 degrees triggers the A/C into operation during QC. Therefore I need to minimize temperatures much hotter than that to insure long life. I know we have a 8 year battery warranty and that batteries degrade over time. With the short range that we already have with the I-MiEV I would hate to lose 20% or more faster then necessary. In summary, my intention wasn't to alarm the owners that come to this site, but to inform them that for those who have the warming system or QC have a simple way to possibly extend the life of their pack without any out of pocket expense or anything that could not be reversed and cause a warranty issue. It would be fine to lock this thread if you want or leave it open to further opinion.
RobertC
Well-known member
Vike said:Thanks for that. But though I bought my i-MiEV w/QC, this is still among the more depressing threads I've read in quite a while. Some of us (i.e., moiJoeS said:
Given the very misleading marketing materials and poor communications, if these cars do develop heat-related problems (which I dare hope they will not), Mitsubishi may find themselves on the wrong side of a (relatively tiny) class action lawsuit.
The i-MiEV battery was developed by Toshiba and uses lithium titanate oxide in its anode.
http://www.toshiba.co.jp/about/press/2011_06/pr1603.htm
The following line is in the press release:
The SCiB™ also generates little heat while recharging, eliminating the need for power to cool the battery module.
The Leaf uses lithium manganese oxide. Here's a comparison test of A123's new battery that shows the Leaf's battery does not do well in the heat.
http://insideevs.com/a123-updates-n...batteries-solves-lithium-battery-heat-issues/
The following line is in this article:
The competition, which is clearly the LMO (lithium manganese oxide) cells found in the Chevy Volt and Nissan LEAF , faired much worse, losing over a third of their capacity.
I still hold out hope that our batteries will stand the test of time.
It's also interesting to note that only the Mitsubishi Motors North America website makes these false claims about battery cooling.
I looked at Mitsubishi websites in the UK, France, Germany, Australia and Japan, and I do not see these claims on their websites.
I don't think that the battery cooling claims were on the website a year ago when I bought my i-MiEV.
I think that MMNA's website has been updated to make these battery cooling claims.
Perhaps MMNA just doesn't know that much about the i-MiEV.
alohart
Well-known member
This does not apply to i-MiEV's sold anywhere outside of Japan, and maybe not even those sold in Japan. The i-MiEV battery is manufactured by the Yuasa-Mitsubishi joint venture, GS Yuasa.RobertC said:
As does the i-MiEV.RobertC said:
Vike
Well-known member
RobertC said:
Confusion on this point is recurring, so the standard reminder:
Toshiba's SCiB has been an i-MiEV battery option for some time now, but only in Japan. SCiB tech stores less energy per pound of battery, but has greatly improved tolerance for being slammed with DC quick chargers. If you L1/L2 charge overnight in your garage, want maximum range between charges, and don't have CHAdeMO stations in your area (i.e., you're a typical American EV owner), SCiBs have little to offer, hence they're not offered in the U.S. While it's also been reported that SCiB can take more charge/discharge cycles and degrade somewhat less over time, over the expected life of a U.S. market i-MiEV neither of these qualities are likely to be enough to compensate for the initial lower energy density and shorter range.
In Japan, where there's a fairly well developed network of CHAdeMO stations, SCiB's reduced range can be worth it if you are able to take advantage of CHAdeMO to quickly top it off, especially since you can safely do that more than once per day if need be. Japanese customers can choose which battery technology they would prefer based on their circumstances; I don't know if SCiB is extra cost.
RobertC
Well-known member
alohart said:
Documentation?
RobertC
Well-known member
I tried the remote AC and the dash controls are ignored and the cold air only comes out the top vents.siai47 said:
I would think that it would be possible to have the AC put cold air into the battery pack when charging at L1 or L2, maybe 5 minutes every hour, when the pack temperature is above 86 degrees.
Small point--it is a Lithium Manganese dioxide cell. The LEV 50-4 and -8's that are in our I-MiEV's are a slightly modified cell that originated from the Yuasa LIM series of commercial Lithium batteries. The first clue that we don't have Toshiba cells in our pack was that the largest Toshiba cell manufactured when our cars were built was a 20 AH cell. It also has different voltage characteristics from the LEV 50. There is no combination of 88 Toshiba cells that would give us a 16 KWH pack at 360 volts. There are also some talk that the batteries in the 787 Dreamliner are the same as the ones in the I-MiEV. Although they are made by Yuasa, they are a Lithium Cobalt cell. Documentation for this came from a Yuasa technical report on the development of the LEV 50 cell and from the material data safety sheets for the cell. The last clue as to what cells we have is that I dropped the pack in one of my I-MiEV's and looked.
One has to think that if MM went through all the trouble developing the cooling/heating system, but only put it into their chaedmo cars, there must be a reason...like, normal battery temps while charging/discharging do not need temperature management...for the battery size and chemistry that we have. We would probably waste more energy cooling our batteries than it was worth.
Again, no hard scientific facts here, but just considering what a group of rational engineers might do.
Consider a Tesla for a moment. They need a thermal management system because they dump so much juice into those massive batteries, that the lights dim in Peoria when a single person turns one on. (OK, I'm stretching it a bit)...but they do use so much juice. The Tesla actually has two charging ports that you must use simultaneously to get any kind of a reasonable charging time. and I think they each pull something like 50 amps, 200 volts.
Again, no hard scientific facts here, but just considering what a group of rational engineers might do.
Consider a Tesla for a moment. They need a thermal management system because they dump so much juice into those massive batteries, that the lights dim in Peoria when a single person turns one on. (OK, I'm stretching it a bit)...but they do use so much juice. The Tesla actually has two charging ports that you must use simultaneously to get any kind of a reasonable charging time. and I think they each pull something like 50 amps, 200 volts.
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