Charging - SOC level differs based on prev. discharge

If OP has reliable access to charging at work, then charging at 80% at home, driving 42 miles to work (ending up about 30% SOC), then charging back up to 80% at work for the drive home should give him a charging cycle that is good for battery longevity.

JRP3 said:

Frankly I'm not sure where you get the idea that taking a small charge out of a lead acid battery then quickly recharging it is a bad thing, it's exactly what every starter battery goes through in a car, and most starter batteries can last 5-10 years.

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Never had a 12V car battery go even close to 10 years...that's a stretch. In Ohio, I had one go 7. Here, you'll be lucky to have one last more than two years. I've been out here for almost 14 years with two different cars...not one battery has lasted more than 2 1/2 years and most went bad around 2. And I always maintained them, even though they say 'no maintenance'.

Extreme heat kills lead acid cells, as does extreme cold. Most people don't see the type of heat you do. My average battery life is around 7 years and I've gotten 10 years, with temps ranging from around -15F to 100F, but much milder averages. If shallow discharge and quick recharging were bad for lead acid I wouldn't be seeing anything like that.

I routinely replace mine at 5 years just for piece of mind and have never had one fail before that point.

JRP3 said:

Extreme heat kills lead acid cells, as does extreme cold. Most people don't see the type of heat you do. My average battery life is around 7 years and I've gotten 10 years, with temps ranging from around -15F to 100F, but much milder averages. If shallow discharge and quick recharging were bad for lead acid I wouldn't be seeing anything like that.

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Lead acid car battery are getting better but they are designed to maintain a full charge.

An EV would have deep cycle battery that are not designed to stay at full charge all the time.

Either way that is an example that has gotten us sidetracked. Yes battery may have slightly more charge immediately after they have been charged and that charge bleeds off rapidly at first but then slows down after that.

This is float charge. For a. 3volt battery tocharge it must be charged with a higher voltage source. This causes the temporary highe rvoltage. It generally provides only a very small boost in range

DaveinOlyWA said:

Lead acid car battery are getting better but they are designed to maintain a full charge.

An EV would have deep cycle battery that are not designed to stay at full charge all the time.

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Deep cycle lead acid batteries also do better when fully charged. They are built with heavier plates to handle a deeper discharge but they also last longer when slightly discharged and quickly recharged.

Either way that is an example that has gotten us sidetracked. Yes battery may have slightly more charge immediately after they have been charged and that charge bleeds off rapidly at first but then slows down after that.

This is float charge. For a. 3volt battery tocharge it must be charged with a higher voltage source. This causes the temporary highe rvoltage. It generally provides only a very small boost in range

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A float charge only applies to lead acid, not lithium, and is simply a low current charged designed to keep a battery topped off. A float charge is not charging a battery that is already near full and then stopping the charge, that's a top off charge. Yes, if his battery is nearly full then adding a little bit more will not add much range, because it's already almost full.

I really don't want to push my luck charging at work. The chief plant engineer already announced he wanted to talk to me about this Leaf charging business. I've been waiting...hiding in plain sight. I cut it off at 58% charge not to push my luck. Well, last night it gave me another shocker. I'm used to losing all bars about 4 miles from the house. I usually get 6 freeway blinking lines miles to make it home. The little sob hit me with the turtle mode just as I was climbing the last 200 yards home. Got me sweatin'. I figured wet pavement, wipers did it in. Now what is starting to bug me is the range. Last year I've read articles where test guys were getting OVER 100 mile range in 40 mph settings. Yeah, right! Nowhere near that number, folks. That's one pipe dream. My average sits at 3.5 and won't budge.
I've got 2000 miles on it and I do want to destroy that battery before the warranty runs out so I truly don't care topping it off and do whatever I need to do to it to get me where I need to go, particularly coming home from work at 11 pm. Folks, I'm not pullling over. It has to make it home. So now I'm charging longer at work - to over 60% because those no-bars miles seem now shorter than they were just 2 weeks ago. I must say today is a dry day and the miles behaved much better coming in, I arrived with 42 smilley miles after a top-off.
Antother thing: I use cruise control. Some contend it's a mile eater. Since I was running out of juice last night, I did the pedal -- ease up, push a little, ease up - you know, a little charging up. I don't think it helped at all. Barely made it up the hill.
So, I wonder now if my battery is factory correct, meaning, are all segments (144 of them?) in working order? Where is that 100 mile range? I love the car, save for the crappy-sounding stereo, but I really thought I was going to make my 82-mile round trip and I'm nowhere near that - short at least 10 miles. So, freeway - we're talking 70 miles max at 66 mph. Am I correct? Is that all it can do?

ILETRIC said:

I really don't want to push my luck charging at work. The chief plant engineer already announced he wanted to talk to me about this Leaf charging business.

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Maybe you can win him over. Offer to pay for the electricity. Ask what the company pays per kWh. On L2 you're probably using about 60 cents per hour. (Much less on L1.) If your car is typically fully or 80% charged after 3 hours that's $1.80. Offer 2 bucks a day. Offer downloads from Carwings of kWh usage to correlate in a spreadsheet with your home charging data to back out kWh day by day.

If he protests that he's not spending all that effort on a spreadsheet for $2, and that he spends more than that per employee on coffee and donuts, agree, and give him a Starbucks card and a box of donuts. Take him for a ride in the car to go get the donuts. Let him drive it back.

Ask if the company has or is seeking LEEDS certification, and show him how EV charging stations earn him points. Show him how to get subsidies for L2 EVSE station installation, on Blink or Chargepoint networks to handle billing at whatever rates he sets.

Yep, ... plus or minus 10 to 20!

You can learn to use it for what it is, or fight it and complain.

You can fill your car a bit more, drive more gently, or ... try to beat it to death. Your choice.

ILETRIC said:

So, freeway - we're talking 70 miles max at 66 mph. Am I correct? Is that all it can do?

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Before you picked up the car the dealer made you sign a four-page "Customer Disclosure Form", and by your signature you acknowledged "that I have carefully read and understand all of the written information contained in this document."

Of course nobody really does read it before signing, but it turns out there is some important information in there, including five range scenarios. The only highway driving case they show is 55 mph in the summer, and their estimated range is ... 70 miles.

So, 70 miles at 66 mph is way more than they told you to expect. Now, their scenario is for 95 degrees with the air conditioner on high, so you should be able to beat it if you keep the A/C down or off, but the undeniable fact is that in an EV speed kills range. You want 80 miles? You'll have to keep your speed under 60. Think you should be able to get 100 miles? Try 45 mph or, as the disclosure sheet says, suburban driving on a mild day with an average speed of 24 mph.

Ray

ILETRIC said:

Since I was running out of juice last night, I did the pedal -- ease up, push a little, ease up - you know, a little charging up. I don't think it helped at all. Barely made it up the hill.

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I'm not sure I understand what you're doing. Please describe what this means.

If you're speeding up on level ground, and then slowing down on level ground to regenerate, that is NOT saving power. You would be wasting power.

If you're slowing down going up a hill, and letting the car coast down the hill to regenerate, that's good.

So, freeway - we're talking 70 miles max at 66 mph. Am I correct? Is that all it can do?

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Yes, that's about right. Check out the "Range Estimate" link in my signature.

Yeah, I looked at that very well made chart linked in this thread. Now I see the real numbers. So I'm absolutely on target with the miles vs. the speed. And my battery is on target, no dead cells. That's a relief. I was wondering...

I trickle charged with 11 bars this a.m. and arrived with 50 smileys at work today which is very nice. Have to do only 2 hrs of charging to bring it up to 60 to make it home with 4-6 miles remaining and one bar. I think the battery likes it too.

I tell you this: wet weather and wipers really kills the range probably more than heat (my estimate). I need to be congnizant of that for my future driving.

I am hoping that in 4-5 years' time I'll be swapping this first gen battery for a double density product (German Kolibri anyone?) and this whole issue will resolve itself. And I am looking forward to Ford EV this fall. Separate radio, folks! Swap for the real thing with a separate amp. Plus cruise control in the 4 o'clock position. And regular analog dials. I mean, who needs those silly trees (max one tree for me) in the speed dial real estate. So Japaneezy. They don't understand our mentality at all. Trust me on this one. I have close contact with Japanese business people. It's a difficult task for them to hit it just right with us.

Love the car though. Saving money and environment. Don't care about the cool factor. Environment. No more burning, no oil changing, easy like a magic carpet. Plus POWER!

JRP3 said:

Extreme heat kills lead acid cells, as does extreme cold.

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Extreme cold does NOT kill lead-acid car batteries. I agree though that high heat does, like here in AZ, but I've had batteries last 7 years in below zero whether where I used to live. I've never had a battery fail because of the extreme cold. All the extreme cold does is reduce your cold cranking amps and makes the car harder to start.

LEAFfan said:

All the extreme cold does is reduce your cold cranking amps and makes the car harder to start.

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Right, which means the battery has to work harder, discharge more deeply, and can lead to early death. I've had more batteries die in the winter than in the summer.

Seriously, the wipers pull VERY little overall... You can barely measure the difference in range with them on.

Rain on the road and in the air, however, will increase drag some, though I haven't seen any concrete numbers as to how much...
When I was driving in the rain many days this winter, I did not see an appreciable difference in range...

ILETRIC said:

Wet weather and wipers really kills the range probably more than heat (my estimate).

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JRP3 said:

LEAFfan said:

All the extreme cold does is reduce your cold cranking amps and makes the car harder to start.

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Right, which means the battery has to work harder, discharge more deeply, and can lead to early death. I've had more batteries die in the winter than in the summer.

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Like I said, I lived in a cold winter state for many years, and never had any trouble making my batteries last. Just because it lowers the amps, doesn't mean it destroys the battery. After the temps rise, it was always as good as new. I always had a digital volt meter to keep watch and keep it in top shape. Here, I haven't had one last 3 years.

Lead acid batteries will freeze in cold if not charged. The freezing will break the plastic case and spill acid all over the place when it thaws.

LEAFfan said:

Here, I haven't had one last 3 years.

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Have you tried a really good AGM such as an Enersys Odyssey, or the Sears Platinum, (Sears' version of the Odyssey)?