Acceptable Battery Loss

[DaveinOlyWA]

Since most of the forum's energy is now concentrated on "unacceptable" battery loss it really begs the question; what is acceptable? now, that is not as easy a question to answer as we might have thought 18 months ago especially now that i am a day short of 18 months and have none. do you feel cheated even if your loss is at a level considered "acceptable" back in Jan 2011?

i guess we should make a poll. keep in mind, all options assume no more than 20% in 5 years or 30% in 10 years. mileage is not dependent here as many studies show time to be the greatest factor assuming a "non abusive" relationship between owner and pack...

1) nothing in first year
2) nothing in first 18 months
3) nothing in first 2 years
4) up to 5% in first 12-18 months
5) up to 10% in first 12-18 months

post your number here, i will up OP as needed

Responses;

1) 1
2) 4
3) 1
4) 6
5) 5


**edit to clarify poll**

the big buzz word is "unacceptable" which means that there was expectation that was not met. this poll is what that expectation was. iow, what were you expecting when you made that purchase decision?

**edit part 2**

hindsight is a wonderful thing but not part of this discussion.

 

[pchilds]

Assuming that loss slows with time.

6% first year,
5% second year,
4% third year, loss of first bar,
3% fourth year,
2% fifth year and beyond,
loss of second bar year six.

This would put you at 20% at five years and 30% at 10 years.

 

[TNleaf]

For those that aren't technical people, if you are going to make a poll like this, you should link in some documentation to help them educate themselves.

Anyone selecting 1-3 should read up on what is PHYSICALLY possible. Otherwise the only way to achieve such goals would to "trick" those users into thinking there have been zero losses (ie, give them WAY more capacity than documented and allow usage of the "extra" capacity as it degrades at it's normal rate, so it looks like there have been no losses).

 

[DaveinOlyWA]

Assuming that loss slows with time.

6% first year,
5% second year,
4% third year, loss of first bar,
3% fourth year,
2% fifth year and beyond,
loss of second bar year six.

This would put you at 20% at five years and 30% at 10 years.

ok u r a "4"

 

[DaveinOlyWA]

For those that aren't technical people, if you are going to make a poll like this, you should link in some documentation to help them educate themselves.

read the information in this forum, or dont read it.

[MOD NOTE: Cut the swearing, please]

oooh DAMN!! someone beat me too it :shock:

 

[Weatherman]

Assuming a t^(1/2) degradation rate and the often-quoted expectation of 80% retention after five years, here's what I'd consider acceptable. This would put me in item #5 on the list:

9% first year
13% second year
16% third year - first bar gone
18% fourth year
20% fifth year
22% sixth year - second bar gone
24% seventh year
25% eighth year
27% ninth year
28% tenth year - third bar gone

 

[TNleaf]

For those that aren't technical people, if you are going to make a poll like this, you should link in some documentation to help them educate themselves.

read the information in this forum, or dont read it. i really dont give F*** what you do

So you don't care if those taking your poll are completely uninformed. Gotcha.

And you respond to constructive criticism with aggressive responses. Thanks. All I needed to know. Nothing informative or useful here, I'll be moving along.

 

[DaveinOlyWA]

For those that aren't technical people, if you are going to make a poll like this, you should link in some documentation to help them educate themselves.

read the information in this forum, or dont read it. i really dont give F*** what you do

So you don't care if those taking your poll are completely uninformed. Gotcha.

And you respond to constructive criticism with aggressive responses. Thanks. All I needed to know. Nothing informative or useful here, I'll be moving along.

this thread is for answering the poll with comments if you like. for criticism of the poll, you are welcome to start your own thread.

as for information; if you choose to pay $35,000+ for a vehicle without getting any information on it. once again, start your own thread. this thread is not to imform people on the chemistry of LI or its reaction to extreme heat, cold or ignorance

 

[adric22]

Count me in with option #4.

Being that I still haven't lost a bar and I've had my Leaf 18 months, I think I'm on track for the acceptable amount of loss.

However, I fully expected when buying the car that after the car is paid off (leasing for 39 months, then plan to refinance for an additional 60 months) I'll probably have about 40 to 50 miles usable range. So assuming the original range was 76 miles then 70% of that would be 53 miles.

After having driven the car for quite some time and having such a short commute, my "range anxiety" right now is right about zero. I suspect even with the lower capacity my range anxiety will still be zero.

Right now I charge to 80% and I still have over 50% charge when I plug in at night. If capacity loss ever starts becoming a problem, I'll just start charging to 100%.

 

[DaveinOlyWA]

Count me in with option #4.

Being that I still haven't lost a bar and I've had my Leaf 18 months, I think I'm on track for the acceptable amount of loss.

However, I fully expected when buying the car that after the car is paid off (leasing for 39 months, then plan to refinance for an additional 60 months) I'll probably have about 40 to 50 miles usable range. So assuming the original range was 76 miles then 70% of that would be 53 miles.

After having driven the car for quite some time and having such a short commute, my "range anxiety" right now is right about zero. I suspect even with the lower capacity my range anxiety will still be zero.

Right now I charge to 80% and I still have over 50% charge when I plug in at night. If capacity loss ever starts becoming a problem, I'll just start charging to 100%.

ya know i am in your boat. i took 4 as well mostly because i blogged about it before i got my LEAF and the fact that i have not seen any yet is a bit shocking to me. but my needs were 50 miles as well and was thinking that is 6-10 years away and was hoping that DCFC network being added to the mix would allow me the same functionality. now that I have 2 in my area, they do help a lot and i find that range anxiety is MUCH better than "paying for gas" anxiety!

 

[bradbissell]

I will go with (5).

Looking at battery profiles for similar chemistries, I assume ~10% in the first year, and then a leveling off with ~1-2% per year until year 10 with 25-30%. After 10 years, there would be a rapid drop off to unusable.

What we are seeing in PX is unacceptable for a battery profile which makes me wonder what was missed, overlooked, or swept under the rug in the testing.

 

[DaveinOlyWA]

I will go with (5).

Looking at battery profiles for similar chemistries, I assume ~10% in the first year, and then a leveling off with ~1-2% per year until year 10 with 25-30%. After 10 years, there would be a rapid drop off to unusable.

What we are seeing in PX is unacceptable for a battery profile which makes me wonder what was missed, overlooked, or swept under the rug in the testing.

this is completely different of course but with my Zenn, my lead acid batteries lost 10% within a month of new, but then leveled off as well (remember total life cycle to under 50% was 2-3 years max!!) so i kinda expected something similar except over a 10 year span

 

[thankyouOB]

My view of acceptable loss would be colored by the cost of replacement.
I can do my commute of 50 miles for some years, and generally want to keep a good, serviceable vehicle for 10 years.
assuming acceptable degradation at 20% after five years, and continuing, I would want to have a cost-effective option for renewing the greater range, as needed.
I would be a four, but hoping for a 2, as I am in coastal climate with no temperature extremes and that definitely was part of my buying decision.

(I am not put off by your remark to the critique, though I would not have gone f-bomb on him.)

 

[DaveinOlyWA]

My view of acceptable loss would be colored by the cost of replacement.
I can do my commute of 50 miles for some years, and generally want to keep a good, serviceable vehicle for 10 years.
assuming acceptable degradation at 20% after five years, and continuing, I would want to have a cost-effective option for renewing the greater range, as needed.
I would be a four, but hoping for a 2, as I am in coastal climate with no temperature extremes and that definitely was part of my buying decision.

(I am not put off by your remark to the critique, though I would not have gone f-bomb on him.)

ok, i make you a 2. after all its a poll of expectations BEFORE you got your LEAF which does make the answer a toughie and FYI; i did not "F-bomb" anyone. it was an "F-star"

 

[kennyboy]

I vote for 4

 

[Stoaty]

I will go with #4 (which is what I am seeing for my Leaf). I am very pleased with my (lack of) capacity loss. #5 might be acceptable too, assuming a rapid slowing of loss after that.

 

[thankyouOB]

My view of acceptable loss would be colored by the cost of replacement.
I can do my commute of 50 miles for some years, and generally want to keep a good, serviceable vehicle for 10 years.
assuming acceptable degradation at 20% after five years, and continuing, I would want to have a cost-effective option for renewing the greater range, as needed.
I would be a four, but hoping for a 2, as I am in coastal climate with no temperature extremes and that definitely was part of my buying decision.

(I am not put off by your remark to the critique, though I would not have gone f-bomb on him.)

ok, i make you a 2. after all its a poll of expectations BEFORE you got your LEAF which does make the answer a toughie and FYI; i did not "F-bomb" anyone. it was an "F-star"

I will take the two.
But i misread your poll.
I thought you were asking for acceptable, now, with more knowledge of the situation.
Perhaps, update the original post and make clear you are asking expectations in Jan. 2011.
but please dont f-star me.

 

[DaveinOlyWA]

My view of acceptable loss would be colored by the cost of replacement.
I can do my commute of 50 miles for some years, and generally want to keep a good, serviceable vehicle for 10 years.
assuming acceptable degradation at 20% after five years, and continuing, I would want to have a cost-effective option for renewing the greater range, as needed.
I would be a four, but hoping for a 2, as I am in coastal climate with no temperature extremes and that definitely was part of my buying decision.

(I am not put off by your remark to the critique, though I would not have gone f-bomb on him.)

ok, i make you a 2. after all its a poll of expectations BEFORE you got your LEAF which does make the answer a toughie and FYI; i did not "F-bomb" anyone. it was an "F-star"

I will take the two.
But i misread your poll.
I thought you were asking for acceptable, now, with more knowledge of the situation.
Perhaps, update the original post and make clear you are asking expectations in Jan. 2011.
but please dont f-star me.

ok, i will update OP, and you are allowed to comment on your poll response if nothing but to clarify. rare is poll that has your exact option so to prevent answers like "2.5" or whatever...ya know so u ok.

if asking what is acceptable now it would be like a compromise. "unacceptable" implies expectation and that is what this poll is about...what were you expecting to see? since you bought the car that implies acceptability of that expectation

 

[thankyouOB]

Dave,
what was your answer?
4?

 

[DaveinOlyWA]

Dave,
what was your answer?
4?

yepper!! i had EXTREME experience with my ZENN (another acronym EV!) with 3 pack replacements in 3½ years. all did the same, they lose about 10% in about a month then the rate slowed way down.

so on my LEAF; i felt i would lose about 5-7% in the first year, about 2-2½% annually after that. i wanted minimum 50 mile range and felt that the public charging system implementation would allow me to get most of that lost range back