Which Lithium ion and Maximising Battery Life?

[AndyInOz]

Hi people,

I've been digging around on the forums, and have failed to find out which Lithium ion battery is in use in the PHEV.

(i.e. specific chemistry).

Similarly, I'm struggling to find instructions, related to the specific chemistry, which describe the best charge/discharge cycle to maximise the life of the PHEV battery pack.

Does anyone have any info?

Andy

 

[Grigou]

Name / Mass proportion (%)

Lithium manganese oxide / 17 - 22

Lithium Nickel Cobalt Manganese Oxide / 7 - 12

Graphite / 8 - 13

Organic electrolyte / 10 - 17


- avoid short charges near 100 % (for example 14 bars --> 16 bars : stay at 14 bars unless you really need 16 bars)
- avoid to stay at 100 % during a long time
- charge at 100 % at least one time in 2 weeks

 

[greendwarf]

Name / Mass proportion (%)

Lithium manganese oxide / 17 - 22

Lithium Nickel Cobalt Manganese Oxide / 7 - 12

Graphite / 8 - 13

Organic electrolyte / 10 - 17


- avoid short charges near 100 % (for example 14 bars --> 16 bars : stay at 14 bars unless you really need 16 bars)
- avoid to stay at 100 % during a long time

- charge at 100 % at least one time in 2 weeks

I assume you mean charge all the way up TO 100% rather continue to apply charge to a full battery :?:

 

[Grigou]

[I assume you mean charge all the way up TO 100% rather continue to apply charge to a full battery :?:

Sorry for my poor english

I meant : "do not repeat charging near the full charge level" (owner's manual, chapter 3 )

I've read that Li-Ion batteries do not like to be at 100 % or near 100 % during a long time : I think that it explanes the manual's advice.

As for me, I often manage to stop the charge at 14 bars because I do not use my car every day.
Why 14 ? Why not ... 13 would be better, 12 better than 13 etc.., but I want to keep an electric car ! :lol:
And if I need a full charge, it doesn't take too time to reach 100 % from 14 bars.

 

[jaapv]

I rather doubt that Mitsubishi's 100% is anywhere near the nominal maximum charge of the batteries in the interest of longevity.

 

[zzcoopej]

I rather doubt that Mitsubishi's 100% is anywhere near the nominal maximum charge of the batteries in the interest of longevity.

I am reaching the same conclusion. According to this article http://pushevs.com/2015/11/04/gs-yuasas-improved-cells-lev50-vs-lev50n/ the battery modules in the PHEV are LEV50N based on this line : "Besides the little EV, these new cells are also used in the Mitsubishi Outlander PHEV." NOTE : This statement was subsequently removed from the linked article so apparently it is not correct, the PHEV uses a LEV40.

The readings we are getting from the PHEV BMU are rarely over about 38Ah even in brand new 2016 PHEV I have only heard of 38.2Ah. The obvious conclusion is that there might be an upper and probably lower band of charge state which is not used?

Interestingly in the 3 months I have been logging the battery capacity of my PHEV using EvBatMon, it has diminished from 36.1Ah on 24/9/15 to 35.5Ah on 21/12/15. So far the decline has been reasonably linear, predicting a 50% reduction to 18Ah by the year 2024 (ie 10 years old). I am currently working on a website which will allow PHEV owners to compare the battery degradation of our PHEVs using EvBatMon, so we can start to see if different driving and charging strategies make any difference.

Note also that the actual SOC can be slightly higher than 100% for a few hours after charging is complete. I believe this is to stop Mitsubishi getting "my car is not fully charging" type complaints. I'm still looking into the range difference between driving immediately after charging vs driving say 12 or 24 hours later, however my initial research is that the difference might be much more than you would expect. Something like 10% more range has been observed if driving immediately after normal charging (ie NOT fastcharge) has finished vs driving 12 hours after charging was complete (which also means the 2pm 12v battery was charged from the drive battery).

 

[anko]

I am reaching the same conclusion. According to this article http://pushevs.com/2015/11/04/gs-yuasas-improved-cells-lev50-vs-lev50n/ the battery modules in the PHEV are LEV50N based on this line : "Besides the little EV, these new cells are also used in the Mitsubishi Outlander PHEV."

That's funny. As they also wrote: "Mitsubishi Outlander PHEV doesn’t use the same LEV50N cells that are in i-MiEV’s battery pack. Instead it uses LEV40 cells. These cells are made specifically for PHEVs." (http://pushevs.com/2015/11/12/gs-yuasa-new-cells/).

BTW: I see no reference to PHEV in the link you posted .....

 

[zzcoopej]

I see no reference to PHEV in the link you posted .....

Guess what, they changed their article, I guess to reflect some inaccurate information. I had copied the entire article into an email as I find it easier to go back to. The article used to say -

... and the retained discharge capacity is 90% after 700 cycles under the condition of D.O.D. 100% at 45 °C.
Besides the little EV, these new cells are also used in the Mitsubishi Outlander PHEV.
These new cells retain 80 % of the initial capacity after 5.500 charge/discharge cycles (100 % DOD @ 25°C).

So now the question is, why the drop from 50Ah to 40Ah, is it lower cost or a "real world" usable DOD vs textbook maximum? Especially when LEV75 are also mentioned, the trend would normally be bigger-better-more!

I will now amend my post like the article it quoted was!

 

[Grigou]

I rather doubt that Mitsubishi's 100% is anywhere near the nominal maximum charge of the batteries in the interest of longevity.

I should be happy if it could be right with a good amount of certainty

But like you, I am in doubt ...

 

[Grigou]

So now the question is, why the drop from 50Ah to 40Ah, is it lower cost or a "real world" usable DOD vs textbook maximum?

See this short discussion here : http://www.myoutlanderphev.com/forum/viewtopic.php?f=10&t=1410

No conclusion ...

 

[HHL]

I rather doubt that Mitsubishi's 100% is anywhere near the nominal maximum charge of the batteries in the interest of longevity.

The readings we are getting from the PHEV BMU are rarely over about 38Ah even in brand new 2016 PHEV I have only heard of 38.2Ah. The obvious conclusion is that there might be an upper and probably lower band of charge state which is not used?

).

I found an MDS on the LEV40 cells and the nominal capacity of these is in fact 38Ah.