Long drive?

I’ve read many people saying that long drives aren’t good for battery longevity. What’s considered a long drive? Is my 32 mile each way highway Maine commute a long drive?

I’ve also read that the answer probably changes with the seasons.

Thanks.

The length of a drive has nothing to do with battery longevity, beyond how it affects the depth of discharge (DoD) of the battery. The only factors that matter to battery longevity are:

* Heat. Hot batteries deteriorate faster, except for batteries like molten sodium that require it. (The Leaf does NOT use a molten sodium battery.)

* Depth of discharge. Lithium batteries are happiest between 20-25% state of charge (SOC) and 80% SOC. Going below 20% isn't considered a major factor in degradation, provided the battery is recharged immediately after the trip.

* Storage State of Charge. Storing a lithium battery at or near 100% SOC is not good for it. This may be the single largest factor in degradation, with many people wanting to keep maximum EV range available at all times. It's much better to keep the car near 50% SOC, with the option reserved to add charge from there if needed. This has become more feasible, as EVs have acquired higher capacity batteries with much more range.

MaineEV said:

I’ve read many people saying that long drives aren’t good for battery longevity. What’s considered a long drive? Is my 32 mile each way highway Maine commute a long drive?

I’ve also read that the answer probably changes with the seasons.

Thanks.

Click to expand...

Well, any rechargeable battery has a planned lifetime of an XXX number of charge/ discharge cycles.

So, those maximum number of charge/ discharge cycles will be reached MOST quickly if you use the battery's entire charge (100% down to 0% or 10%) and then recharge/ discharge again the next day...

If you only drive the car and use a partial charge range of the battery (e.g., 60% to 40%) and then charge again to 60%, there will be minimum "wear" on the battery. Then the battery may last 2X or more number of charges.

SO, if you daily drain the battery down significantly, you will wear out the battery than if you only partially use the battery daily.. For example, construction contractors use their cordless drills so much that they use up their rechargeable batteries in only a few months, where a casual user will use the battery in a drill for years...

powersurge said:

Well, any rechargeable battery has a planned lifetime of an XXX number of charge/ discharge cycles.

Click to expand...

A Li-ion battery I have good test data on can do about 400 100% to 0% cycles to 80% capacity.
Or could do about 2000 100% to 50% cycles. Again to 80% capacity.
That's about 1000 "equivalent full cycles". Or about 2.5X the number of miles driven.

powersurge said:

If you only drive the car and use a partial charge range of the battery (e.g., 60% to 40%) and then charge again to 60%, there will be minimum "wear" on the battery. Then the battery may last 2X or more number of charges.

Click to expand...

A 60% to 40% cycle is even better. More like 4500 equivalent full cycles. Or about 11X the number of miles driven.

powersurge said:

SO, if you daily drain the battery down significantly, you will wear out the battery than if you only partially use the battery daily.. For example, construction contractors use their cordless drills so much that they use up their rechargeable batteries in only a few months, where a casual user will use the battery in a drill for years...

Click to expand...

Yep. And if they could learn to use only half of the battery before swapping, their batteries would last much longer.

LeftieBiker said:

* Depth of discharge. Lithium batteries are happiest between 20-25% state of charge (SOC) and 80% SOC. Going below 20% isn't considered a major factor in degradation, provided the battery is recharged immediately after the trip.

Click to expand...

Thanks for all the info.

Should I let the battery cool down some before recharging? Would my 30 something highway commute increase the battery temp?

MaineEV said:

I’ve read many people saying that long drives aren’t good for battery longevity. What’s considered a long drive? Is my 32 mile each way highway Maine commute a long drive?

I’ve also read that the answer probably changes with the seasons.

Thanks.

Click to expand...

Long drive is 2x your full range or more in one swoop. 64 mile round trip commute is nothing to worry about.

Your battery temperature would increase just a nominal amount and have plenty of time to cool.

Should I let the battery cool down some before recharging? Would my 30 something highway commute increase the battery temp?

Click to expand...

Don't assume that the battery will get hot on that short trip, as it likely won't, as noted above. If the weather is really hot, or it's 30 miles of climbing a mountain, then the battery may get hot for that reason. Bring up the battery temp gauge and if it goes beyond the left 1/2 of the range, let it cool to 1/2 before recharging. If you run the battery below 20%, then charge it to 25% or so while hot (don't use a quick charge station) and then let it cool before finishing.

You can always open the battery access door in the back seat floor and dump ice down on top of the battery.
It's crude but effective.

Is it really that hot there already?
I lived in Maine for 4 years.

Oilpan4 said:

You can always open the battery access door in the back seat floor and dump ice down on top of the battery.
It's crude but effective.

Click to expand...

Have you actually done this? There's a giant air gap between the cells and the shell. Dumped ice is not likely to do much, but a few gallons of chilled water a minute might help.

Guys, let's please not try to make new Leaf drivers think that they need to chill their batteries with ice or ice water.

^^^
Agreed.

smkettner said:

Long drive is 2x your full range or more in one swoop. 64 mile round trip commute is nothing to worry about.

Your battery temperature would increase just a nominal amount and have plenty of time to cool.

Click to expand...

Yep.

OP, if you are really curious, just monitor battery temps with Leaf Spy. You'll see what we're talking about. If the OP really wants to cook their battery, on a hot day, DC fast charge it on a DC FC that's rated at over 50 kW from empty for an hour.

You can always open the battery access door in the back seat floor and dump ice down on top of the battery.
It's crude but effective.

Click to expand...

Please, any new LEAF owners... do not believe this.

Maybe only of your are back to back quick charging it and running your leaf down the highway.