Li-ion Battery DETROYED by DEEP DISCHARGE

• . The Tesla Motors’ Roadster

If the battery is ever totally discharged, the owner is left with what Tesla describes as a “brick”: a completely immobile vehicle that cannot be started or even pushed down the street.

• . . . From; http://slashdot.org/submission/1953457/how-to-brick-an-electric-car

Of the approximately 2,200 Roadsters sold to date, at least five Roadsters have been “bricked” due to battery depletion that can only be repaired by paying Tesla $40,000 to replace the entire battery and the damage is not covered by warranty (PDF). Behind the scenes Tesla has seemingly been scrambling to try to ensure existing owners don’t “brick” their cars.

After the first 500 Roadsters, Tesla added a remote monitoring system to their vehicles that Tesla uses to monitor various vehicle metrics including the battery charge levels and Tesla has used this information on multiple occasions to proactively telephone customers to warn them when their Roadster’s battery was dangerously low. "

In at least one case, Tesla went even further. The Tesla service manager admitted that, unable to contact an owner by phone, Tesla remotely activated a dying vehicle’s GPS to determine its location and then dispatched Tesla staff to go there," writes DeGusta. "Going to these lengths could be seen as customer service, but it would also seem to fit with an internal awareness at Tesla of the gravity of the “bricking” problem, and the potentially disastrous public relations and sales fallout that could result from it becoming more broadly known."

I've read threads on this apparently Tesla specific issue on both Prius and
LEAF forums.

I'm interested in what Mitsubishi has to say about low HV battery conditions
for the i -- cautions, warnings, recommendations, whatever.

So, I went looking for an i Owners Manual on the Inter-web. And as posted
elsewhere, I found that it is nowhere to be found in the virtual world.

I'd ask that current i owners provide text or scans of the relevant parts of
the Manual so that potential i buyers -- like me -- can understand how
Mitsubishi handles potential "bricking" conditions in the i.

{Edit}
After 30 pages of Google results, I did find this:

Mitsubishi i-MiEV
In the i-MiEV’s warranty manual, Mitsubishi states that the standard warranty
does not cover any damages to the Li-Ion battery resulting from “failure to
keep the main drive lithium-ion battery charged during storage of the vehicle.”
John Arnone a representative from Mitsubishi, said that while the i-MiEV
battery can be fully discharged, if left for a long period of time it will still be
able to be recharged by the usual means.
http://www.autoguide.com/auto-news/category/manufacturers/mitsubishi

I'd still like to see what the Owner's Manual has to say.

A non-issue in everyday life IMO, as it's sensationalist "journalism" picked up by the media. Credit Tesla with being pro-active in tackling this.

I'll let someone else dig out the iMiEV manual and its overload of lawyeristic CYA statements.

Yes, fully discharging a battery pack, or allowing it to get fully discharged, is cruel and unusual treatment of the cells. Leaving an EV discharged after driving the pack way down is negligent, IMO.

When driving, based upon what I've seen so far, it seems to me that the iMiEV BMS has plenty of safeguards built into it to preclude deep-discharge (or overcharge) damage.

When storing an iMiEV unused for a long time, wouldn't one either have someone come over periodically to check it and recharge if necessary or perhaps set up some sort of an automatic timer to periodically top it up?

It's not like this happens within a matter of days or even weeks... nevertheless, it would be interesting to measure the iMiEV's quiescent power OFF discharge current of both the main battery pack and the 12v battery (powering active alarm system) in order to get a quantitative handle on this. Hmm, does anyone know if the dc-dc converter stay active with power off?

I got this from Mitsu on Saturday 25th.

Yes, I also received the same letter on Saturday. Just another way of ensuring that the BMS and SOC are periodically recalibrated. Glad to see Mitsubishi is on top of this. Interesting that they're calling the Fuel Gauge a SOC indicator instead of the Energy Level Gauge in their manual. Traditionally, SOC is usually expressed as a percentage from 100% full to 0% empty. Hey, our battery pack Fuel Gauge has better resolution than the Leaf's!

FWIW:

Q. Are all types of electric car batteries potential victims of total irreversible failure?
A. All batteries will eventually fail if left to drain slowly for many years, but bricking
is avoidable with a fail-safe provision that could sustain some level of charge for years.

Nissan said in a statement that the Leaf’s battery pack “will never discharge completely,
thanks to an advanced battery-management system designed to protect the battery
from damage.”

And, said a Nissan spokeswoman, Katherine Zachary, “Never means never.”

New York Times

Well,I also learned about the claim of this blogger named Michael Degusta that letting Tesla Motors Roadster’s 53-kilowatt-hour lithium-ion battery pack run down will destroy the power source and make the car useless. He actually called this brick,In electronics, “bricking” means to render a device no longer functional. Tesla says the issue is one of maintenance, not unsound engineering. Anyways, from what I gathered, Replacing the battery pack in the Roadster could already cost as much as $40,000.

In electronics, "bricking" means to make a gadget so that it can no longer be used for its intended reason. More than one Tesla Roadster owner has said recently that the vehicle can grow to be a "brick" if simply left unplugged. Tesla, however, states the owners are at fault, not the automaker.

In my opinion this is a complete non-issue with us who use our cars daily, and should certainly not be a concern to anyone considering buying an electric car! The iMiEV's BMS is smart enough to keep us from destructively discharging the battery pack even if we're careless enough to run it all the way down!

It's only if you store the car unused for a significant period of time (like months) that you should make some provision to periodically have someone check the fuel gauge and charge the battery pack if needbe. Just as with a stored ICE or hybrid car, I would want someone to take it for a run around the block occasionally.

I would agree with JoeS's assessment of this as media sensationalism. The problem occurred with .002% of Tesla's production run, and was a result of owner neglect. I'm sure the vehicle's battery management system prevents a total discharge by operating the vehicle. So these were cars that were driven down, then parked for an extended period of time without being charged.

Our 2007 Zenn (LSV) was stored during Michigan winters. It used lead-acid batteries (AGMs), and the factory advice was to simply leave the car plugged in during storage. While it was a relatively primitive EV, the Zenn's on board charger was smart enough to top off the pack when battery levels fell to 80% in storage.

Bricking a battery pack makes for a fun news story to disparage EVs. The reality is that it is a non issue, aside from owner stupidity.

Does Mitsubishi have some protection on their i-Miev? I guess even protection doesn't help if the owner completely discharges and then leaves it sit for an extended period of time.

The Turtle is our friend and will prevent damage.

We never met her before. Karin and me usually try to get home or find a place to charge when the meter gets near half.

We grew confident and tried to reach a party convention of the pirates. First stop after 15 kilometers. Next stop after another 80 kilometers. We grew a bit nervous because our i-MiEV was not used to highways and took more reserves than we guesstimated. The Turtle warned us and we reached our socket in time. Next stop would be 111 kilometers. Again the Turtle showed and we could not find a free socket at our destination. The convention saved us. 400V 32A (that is actually 3 phase with 240V each of them) out of the townhall helped us on our way back. Again the Turtle showed at the end of 111 kilometers, telling us next time to reserve two bars or 20 kilometers for her. We promissed.

Either she was satisfied or it was to cold for her to show up again. After a frosty night we reached our home skipping the final socket. We still had 2 bars left.

We were told, if you never met the Turtle, you dont know how to drive an i-MiEV. On the other hand the Turtle always brought them home - after promissing.

For people not believing in the Turtle spirit, the i-MiEV has got a battery management system.

Oh, I've met the turtle on more than one occasion. It's really not so bad, if it were I'd suggest they use a different icon. I just follow known sound advice, I get off the expressway and avoid any hard acceleration, reducing speeds to 40km or less. I've never run the battery completly down to where the car was undrivable.

some of the more technical members might be able to confirm this. Its my understanding that we only have access to about 92% of the actual capacity. I suspect Mitsubishi reserved the other 8% for battery life support and to ward off this very issue of full discharge.

Pretty clever.