Charging Model S using 110 increases range

[Dan5]

Found out something yesterday and thought it would be useful.

Charging at 110 V helps load level the pack, apparently if you use the 110V to charge instead of the 220/240 or 480 the rated mileage will increase.

It will not do it during the first charge and will take months to get it, but I heard from a Tesla rep that the journalist cars almost always plug in using the 110 and they are getting over 300 miles of rated range per charge.

I guess the takeaway is that if you can use a 110, use that to charge the car.

I'm going to be doing that from now one, it may take a while to charge, but it's OK.

 

[dhrivnak]

We see this on the Roadster as well. The differences are small. That is one reason that while I can charge at 70 amps i normally use s slower rate.

 

[joshuaeven]

Really? I thought the common practice was to use the 14-50 for more efficient charging. I'd like to see something official that states, basically, use the slowest charging you can get away with.

 

[dsm363]

Really? I thought the common practice was to use the 14-50 for more efficient charging. I'd like to see something official that states, basically, use the slowest charging you can get away with.

That still holds but for whatever reason, after a slow 110V charge you seem to get a few extra miles of range. That doesn't mean it is more efficient though as for the Roadster a least, Tom showed less overhead at 40A I believe.
Tesla Roadster Charging Rates and Efficiency - Tom Saxton's Blog

 

[wycolo]

What, plug in all night on 110vac starting with a range charge of 270 miles just to add 5 or 6 miles max? If that? I prefer to add the 'partial-range' or 'full-range' just before embarking. That way it is deployed within the first 30 or 50 miles of the trip.

This car spends most of its life sitting plugged into 240vac. If it chooses to balance the batteries it has ample opportunity. Disconnecting one leg of that supply is now supposed to become therapeutic??

Also, the final 30 - 45 minutes of a 240vac full range charge is intermittent: on, off, on, off, while battery balancing is taking place. Bit of a time waster unless you really do need those miles and can't get them somewhere on a recharge.
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[WarpedOne]

This is not that hard to understand just ask yourself this: how does a charger know when the battery is full?

It "knows" this by observing the floating i.e. the battery's own voltage and resistance.
When it charges it must push this voltage higher for current to flow through the battery. Higher the charging power, bigger the difference between charger's and battery's floating voltage needs to be.
Immediately after charging battery looks more full than it really is. After some time the floating voltage will drop a few mV and then stabilize.

Higher the charging power, bigger the drop in floating voltage after the charging. Or in other words - charging slower sneaks a bit more energy into to the battery.
It is not about 110V or 220V charging, it is about power.

 

[qwk]

True story. My car gained about 8 miles of rated range over about a month's time of charging on 110v(standard mode). I don't know if charging in range mode on 110v is a good idea, because the car will sit at a high state of charge for a very long time(it takes over 12 hours of charging on 110v to go from standard to range mode).

 

[Dan5]

This is not that hard to understand just ask yourself this: how does a charger know when the battery is full?

It "knows" this by observing the floating i.e. the battery's own voltage and resistance.
When it charges it must push this voltage higher for current to flow through the battery. Higher the charging power, bigger the difference between charger's and battery's floating voltage needs to be.
Immediately after charging battery looks more full than it really is. After some time the floating voltage will drop a few mV and then stabilize.

Higher the charging power, bigger the drop in floating voltage after the charging. Or in other words - charging slower sneaks a bit more energy into to the battery.
It is not about 110V or 220V charging, it is about power.

Yes, I think that's what the Tesla employee was explaining, that it trickle charges and gets a little more energy into the battery, and when some cells are completely charged, it stops charging, while other cells still have a tad bit more to go to completely charged.

I agree, I don't want to put in range mode, but for daily driving, the 110 seems to be the best.

With the 220, you do charge faster and it is more efficient charging, but from a battery longevity standpoint the 110 is the better option.

There were a few other owners who heard this and it was a good discussion concerning which type of charging is best for the battery.

 

[islandbayy]

You do not specifically need to use a 110 outlet to do this.
A 220/240v outlet, set all the way down to the minimum 5 amps, would be the same as 110/120v outlet charging at 10 amps, or 6 on the 220 would be like 12 on the 110. Just dial the amperage down. Does not matter what the input voltage into the charger is, as the charger designates the output voltage anyways. But the lower amperage will allow you to sneek more juce into the pack. It will also allow for better pack equalization.

 

[100thMonkey]

that's my understanding, that slower charging allows for more time for the voltage to equalize throughout the cell before tripping the BMS to stop charging. this could also be achieved by charging the battery to full quickly, let the voltage spread throughout each cell to a lower voltage and then top off.

slower charging is less efficient, it has the battery sit at a higher SOC for longer periods while it finishes and theoretically you would end up with a higher overall resting voltage which would accelerate cladding/electrolyte degredation, aka shorten battery life over the long run.

I personally wouldn't do this every day, but when I've needed to pack in the extra electrons with the Leaf, on rare occasion I will go against manufacturers recommendations and top off after a settling period, but I do it all at 240. I don't let the battery sit like this for very long so I figure it has minimal long term effect on life... and still nothing compared to the effect of high ambient temps.

This is not that hard to understand just ask yourself this: how does a charger know when the battery is full?

It "knows" this by observing the floating i.e. the battery's own voltage and resistance.
When it charges it must push this voltage higher for current to flow through the battery. Higher the charging power, bigger the difference between charger's and battery's floating voltage needs to be.
Immediately after charging battery looks more full than it really is. After some time the floating voltage will drop a few mV and then stabilize.

Higher the charging power, bigger the drop in floating voltage after the charging. Or in other words - charging slower sneaks a bit more energy into to the battery.
It is not about 110V or 220V charging, it is about power.

- - - Updated - - -

I'd be very surprised if 110 charging is found to improve long term cycle life. it would keep the battery cooler but also tend to keep it at a higher energy level for longer, which would likely reduce long term cycle life. my understanding it that it can increase how much energy you can pack into the battery in a charge but everything I've studied states that higher energy levels increase degradation in the long run. fast charging with topping off right before departing would likely be the better bet.

Yes, I think that's what the Tesla employee was explaining, that it trickle charges and gets a little more energy into the battery, and when some cells are completely charged, it stops charging, while other cells still have a tad bit more to go to completely charged.

I agree, I don't want to put in range mode, but for daily driving, the 110 seems to be the best.

With the 220, you do charge faster and it is more efficient charging, but from a battery longevity standpoint the 110 is the better option.

There were a few other owners who heard this and it was a good discussion concerning which type of charging is best for the battery.

 

[mitch672]

With 4.5, I now only charge to about %70 (168 miles), I normally just drive 45-50 miles / day, so this ends up cycling the pack from about %70 down to about %50 (120 miles or so). I'm not concerned with seeking out every possible mile, but for long term battery health a SOC in the middle of the range is supposed to be less stressful on the pack.. As a bonus, it has full regen because there is some room to accept additional charge immediately. Carry on

 

[Dan5]

To clarify, its not taking it to 100% charge with a 110 all the time.
Its taking it to your specified percentage with the 110.

I guess the best analogy is you have a bucket of water and want to fill up cups with a pump. So when you see the average watee level reach a certain height on the cups you turn off the pump.

Some cups have more, some less. If you decrease the water flow, you get a more even spread since the flow is less.

Same premise for the battery, it stops when it sees the average at a certain amount, BUT not every cell is at the average. The closer you are the the average as individual cells the more range you have. Its counter intuitive, and that sparked a huge discussion, but for cell longvity it does make sense.

Also with the 110 the C rating is lower so the batteries should last longer.
I have a 220 in my garage which i had installed and am probably only going to use it for emergencies now.

 

[stevezzzz]

...the lower amperage will allow you to sneek more juce into the pack. It will also allow for better pack equalization.

Which brings up a question for the OP: why do you want to 'sneak a little more juice into the pack?' That can't be good for the pack over the long haul. Or do you mean to do it only occasionally, so that when you do need a max charge you'll have a few more miles of range?

 

[stopcrazypp]

Which brings up a question for the OP: why do you want to 'sneak a little more juice into the pack?' That can't be good for the pack over the long haul. Or do you mean to do it only occasionally, so that when you do need a max charge you'll have a few more miles of range?

It's not worth the extra charge time, energy losses, and impact on the battery (keeping it at high SOCs for long periods) to do this regularly.

But it's a good thing to do occasionally since your pack will drift out of balance as time passes (and as seen one other thread, this can cause some hair pulling by mistaking this as battery degradation rather than an out of balance battery).