Clarity life after 50596 miles

This has become buried within this thread. Maybe I should start a new thread specifically to disseminate this...

 

Either disseminate it, or get some owners to try the test on their batteries.

It would be nice to get some more experience with this.

One problem is that nobody wants to be the battery that is in poor condition, sometimes ignorance is bliss.

 

Au contraire -- A poor battery means a free replacement !!!

 

A bad battery is replacement, a poor battery (less than good) is just bad news...

 

My designation of 'poor' is really 'bad'... Maybe a poor choice of wording !

 

I've backed out of this debate for a number of reasons (still gathering more test data). However I wanted to mention something that I didn't put "two and two" together on until this evening while browsing an unrelated thread. Seems we get a lot of repeat questions, repeat discussions, and repeat answers in this forum - often due to the lack of use of the "search" function. I found this by accident... In the several threads of using a PHEV as an emergency power supply (12V inverter) for your house, people debated the capability of the DC-DC converter. This had been addressed a lot, however someone (Garry2) found an actual document that gave a power rating. Annoyingly, it is an SAE published document, so not even on the Honda Tech resource site. However for $33 a copy can be yours... However until I find a source that isn't on the SAE site I cannot post a copy here - they track that crap and are serious about enforcement!

https://doi.org/10.4271/2018-01-1184

I was so happy to see this document. Anyway, the thing I found most interesting is the substantial reduction in HV battery life as tested by Honda if the EWV (electronic water valve) is not functioning correctly or not used. I have usually espoused the importance of thermal management and battery temperature as the greatest impact on battery life (above charge and discharge parameters alone) seems this graph shows that is dramatic. They also discuss the impacts that ESR plays in this thermal management (I've mentioned that before, but this proves they have that in the BMS). This also puts to rest all questions regarding the battery specifications at the time of publication. Some I had wrong!

The graph provided is not "technical" in that it doesn't state the scale used or parameters. However assuming the graph is relevant to itself, then the failure of the EWV/Cooling system will shorten the life of the battery in the Clarity by around 15% (33% loss is warranty <8 years, so that is almost half that amount). Anyway, just found that interesting considering the 18-090 Service Bulletin that was specifically for a malfunctioning water valve software control. I am guessing here, however I would be willing to bet that failure to comply with that bulletin would directly impact your HV Battery warranty. As Kentucky has discussed, there are laws out there saying that something you do has to be shown to impact a component to effect warranty of it - I don't think Honda even mentions the HV pack in that recall bulletin, however considering their data - maybe they should have.

Just speculation.

Cheers,

Cash

 

I just charged mine at a ChargePoint 6.6 kw public charger. Used 13.478 kWh for full charge from 9% SOC.

I had previously reported that it took 12.84 kWh to charge with the Honda charger from 11% SOC.

I expected the Level 2 charger to use less kWh than the Level 1, from the previous discussion on this thread...

 

Well, this is obviously not an exact science.

I think the basic technique still makes sense from the standpoint of roughly assessing where you may be on the curve towards battery 'failure' (good, fair, poor, or similar). If you want to know your battery capacity with greater precision than that, then I suggest that you need to be watching the trend from a large number of charges. Furthermore, it is better if the data is from the same EVSE setup (eliminates further variability from a multitude of charger setups and operating currents). I felt like the graph I showed earlier (a composite of 200 charges) allowed me to do this average quite well just with the eyeball. All of those points were with the same EVSE setup so the 18 month trend is very apparent and believable.

At least this simple method can give you a feel for whether it is worth a trip to the dealer for a readout of the actual capacity. I assume the vehicle capacity report also includes some kind of filtering such that you would not get a different number every time you pulled it.

Ultimately everyone here would dearly love to be able to pull the number from the vehicle ourselves. There is currently a $380 tool that can do this, and there is hope for a $60 tool with future software updates. @Cash Traylor is working on coming up with something on his own using a Panda. If we eventually get an affordable solution to read out the actual capacity, this all becomes moot.