Consider this is the kick-off post for the Sub-80% Club
I'm guessing that I am not the only one here who rarely charges the LEAF to 80% and/or lets it sit mostly at lower SOCs. This is the place to discuss the whys, the hows, the expectations and the drawbacks related to maintaining the LEAF battery SOC below 80% most of the time.
I have come to believe that so-called "Long-life Mode" in the LEAF may not offer much additional battery life versus charging to full. This is particularly true for those of us who do not drive the car each day and typically do not travel very far when we do drive. The LEAF has plenty of range for most of our trips, but if we simply used 80% charging and plugged in each day, the battery would spend most of its time almost fully charged.
There are two main techniques which we use around here to try to maximize the battery life in our LEAF:
- Just-in-time charging: The LEAF is ONLY charged just before it is to be driven.
- End-of-trip SOC targeting: The SOC the LEAF is charged to is based on discharging the LEAF to three charge bars upon returning home. This is the charge level at which we would prefer the LEAF spend most of its time.
In practice, we do this by setting an 80% charge timer for each morning at 8:00AM.
- If we do not plan to drive the next day, the LEAF does not get plugged in.
- If we need more than about 7 bars of charge the next morning, we plug the car in the evening before. If the target is 10 bars, we're done. If the target is 7 to 9 bars, we simply unplug in the morning when it is at the correct level. If the target is full, then we override the timer to get it full. (This is fine if we are leaving after about 10:00AM. Otherwise, we need to override early in the morning or the night before.)
- If we are driving in the afternoon or need fewer than 7 bars for a trip, we simply press the charge override button a bit before we depart so that it gains the proper number of bars. I use about 2.5 bars/hour for the estimate.
By targeting 30% to 40% SOC for most of our LEAF's resting life, we hope to maximize battery life. Using estimates from Stoaty's LEAF Battery Aging Model
we estimate this means 15 to 20 years of life, perhaps even more. Is this expectation reasonable? We really have no way to know. Only time will tell.
- This approach is a bit fiddly. It sure would be great if Nissan would allow us some more flexibility in setting up charging endpoints, etc. Several of us have requested this, but so far there has been no enhancement in this area.
- Our LEAF does not sit in a "ready to go" state. As a result, if something comes up on the spur of the moment, either we need to take another vehicle or we will end up running down the LEAF battery further than we should for best battery life. This latter issue can also arise if we use more charge for a given trip because of other factors such as weather, side trips or inefficient driving.
Are you in the Sub-80% Club
? If so, please tell us why and how you manage. Perhaps we can all learn something from the exchange.