Best practices for charging?

[StrangePenguin]

Hi, I'm the new owner of a 2020 Clarity Plug-in.

Sorry if this question has been asked before -- I am wondering if there is a consensus for best charging practices in order to maintain battery life.

In our current situation of working from home, nobody in our household is commuting, so there will be a lot of days with either no driving at all or just driving a few miles (for example, 2 miles roundtrip to the grocery store).

The manual says, "To help extend the lifespan of the battery, it is recommended that you fully charge the battery each time prior to driving." That would imply that even if we drive <5 miles in a day, we should plug the car in and "top up" the battery.

However some other web pages about EVs that I found warn against keeping them full all of the time. (for example: https://www.motortrend.com/news/ev-lithium-ion-battery-life-tips-tricks-advice/ ).

So I'm wondering if the manual is off-base with the recommendation to always top up the battery?

 

[ClarityDoc]

They're just saying don't leave it depleted. If it hasn't been driven much at all since last charge a few days ago, you don't need to worry about charging it.

 

[JFon101231]

Agree. In that example I wouldn't charge every day either, maybe once a week - keeping it under 100% should also avoid the ICE kicking in when you dont want it to just to disperse excess regen

 

[Landshark]

So I'm wondering if the manual is off-base with the recommendation to always top up the battery?

The manual is wonderfully vague in so many ways. We all have different driving patterns. You drive 2 miles a day and could easily go a few weeks between charges. I typically drive 40-50 miles a day, using most or all of the available battery capacity and fully charge every day.

Honda didn’t make the effort to explain ideal charging protocols for every possible situation. They probably figured the average driver would travel 20-30 miles a day, so they recommend fully charging prior to each trip.

If I were in your situation, I would fully charge the battery every 2-3 weeks, mostly to avoid the minor inconvenience of having to plug in the cable every day.

 

[insightman]

Does Honda really believe people will do all the things they recommend in the Owners Manual?

• To help extend the lifespan of the battery, it is recommended that you fully charge the battery each time prior to driving. (page 466)
• We recommend that you check the engine oil level every time you refuel or you charge the High Voltage battery. (page 483)
• We recommend you check the engine coolant level every time you refuel or you charge the High Voltage battery. (page 488)

 

[MrFixit]

I would offer a simple suggestion - Use whatever charging regimen fits your usage and convenience.

You will find a lot of opinions from those who feel they have more technical knowledge than the Honda engineering team.
The only thing I would intentionally avoid is deep depletion of the battery (below the normal 2-bar minimum). The vehicle generally prevents this, but you can do dumb things to force depletion. If I knew I wasn't going to drive the vehicle for an extended period (maybe a week or more), I might plan to do this with a charge level that's somewhere in the middle of the range.

 

[Landshark]

Does Honda really believe people will do all the things they recommend in the Owners Manual?

There’s really no telling what Honda believes and they certainly have a reputation for not letting us know. They are recommendations not requirements. We learn through experience when recommendations become necessities.

As an example, my car recently sat unused for 6 months. At the end of those 6 months the tire pressure was only 1psi below the pressure that was set 6 months earlier and that was on just 2 of the tires. Do I need to check tire pressure prior to each trip? No. I base that decision on knowledge gained from past experiences.

To the original question of battery charging, I don’t believe it will amount to a hill of beans over the years whether the OP charges every night or once a month.

 

[Danks]

Does Honda really believe people will do all the things they recommend in the Owners Manual?

• To help extend the lifespan of the battery, it is recommended that you fully charge the battery each time prior to driving. (page 466)
• We recommend that you check the engine oil level every time you refuel or you charge the High Voltage battery. (page 483)
• We recommend you check the engine coolant level every time you refuel or you charge the High Voltage battery. (page 488)

Ha. I quickly learned not to change every time prior to driving when I got my first electric bill after getting the Clarity. Now our routine is to charge at home where we pay for it only when we have to. My wife gets free charging at work 2-3 days a week and we have 3 free L2 chargers about 4-7 miles away from us. I will typically take the car to one of the free stations once or twice a week to get my wife enough electrons to get to work to charge there.