Accessing 100% of the battery

[PowerstrokeNC]

Anybody made any attempts to find out how to access 100% of the battery capacity? I was just reading an article on the VW Golf E and it has a 24kWH batt and is said to go 115 miles. That kind of mileage should be achievable for the FFE if we had ALL the battery.

I know long term battery life could suffer but it should would be nice to be able to choose, ie when making a longer trip.

 

[PowerstrokeNC]

Nobody? :shock:

 

[user 3729]

The simple answer is the e-Golf won't go 115 miles unless you set the cruise control on 38mph on a flat road with A/C off and 70-degree weather outside. It's just a misleading spec.

 

[WattsUp]

The FFE will go 115 miles too, if you drive using 169 Wh/mi, which is probably somewhere well under 25 mph.

 

[PowerstrokeNC]

Am I correct though that the Leaf can be charged to 100% of batt capacity and not just 80% like in the FFE?

If the answer is yes, then is there a way for us to access the additional 20% of our batteries capacity? Either by a reprogram or hack of some sort?

This is my first electric car, but previous to this I have had several small displacement turbo ICE cars mostly of the VW and Audi variety.

There were many options available aftermarket to reprogram the ECU to alter fuel & boost levels to achieve a variety of gains either in MPG or HP output.

Now I know this is obviously something the manufacturer didn't intend and probably doesn't warranty, I don't need someone to point that out for me.

What I want to know is has anybody looked at this option? It would be aftermarket performance for EV's LOL!

 

[WattsUp]

Am I correct though that the Leaf can be charged to 100% of batt capacity and not just 80% like in the FFE?

Yes, the Leaf has an option to charge to 100% of its battery capacity. However, you are not correct about the FFE only charging to 80% of its capacity. From what I can surmise, the FFE actually charges to about 95% of its battery capacity. There is really not much more to be gained by pushing it to 100%, something which can damage the battery under certain circumstances (and which is probably why Ford does not provide the option).

The stated total capacity of the FFE battery pack is 23 kWh. By all accounts, the usable capacity seems to be 19.5 kWh (which is already more than 80%, btw). As is common for lithium-ion battery applications, I suspect the FFE probably avoids discharging the battery much below 10% (2.3 kWh), which provides a "buffer" to avoid chemically damaging the battery from full discharge.

So, we have:

19.5 kWh (usable) + 2.3 kWh (buffer) = 21.8 kWh (stored energy) = ~95% of 23 kWh

Thus, on a "full charge", the FFE battery is almost certainly significantly over 90% capacity. Truly charging to 100% would only provide around 1 kWh more of usable energy, which would yield a nominal range of 80 miles instead of 76.

 

[sourcejockey]

Ack, I just read this right after I posted about this... I had a conversation with Ford Corporate, and the battery will not go below 20-30%. I'm rather aggravated about this, as I was told the battery had 23kWh to use; I can only use 16 before my car SSNs on me.

 

[unplugged]

Ack, I just read this right after I posted about this... I had a conversation with Ford Corporate, and the battery will not go below 20-30%. I'm rather aggravated about this, as I was told the battery had 23kWh to use; I can only use 16 before my car SSNs on me.

Well, it's not like advertising 123 horsepower and finding out after the purchase you only get 116. But I suppose car manufacturers could sell the battery like hard drive or flash memory and tell buyers the product only has 16 or 19 or whatever of usable battery capacity.

 

[WattsUp]

Ack, I just read this right after I posted about this... I had a conversation with Ford Corporate, and the battery will not go below 20-30%. I'm rather aggravated about this, as I was told the battery had 23kWh to use; I can only use 16 before my car SSNs on me.

So you're saying 20-30% of the battery is not available for use in the FFE? That doesn't seem quite right. The usable battery capacity of the FFE, by all accounts, is about 19.5 kWh, which does not align with 20-30% of the battery being "unusable".

The 20-30% figure seems incorrect based on multiple experiences here, including my own. If we average (your figure of 20-30%) to 25%, meaning 75% of the battery can be used, that comes to only 17.25 kWh (of the total 23 kWh), which is quite a bit less than folks have been able to use.

It seems to me that about 15% of the FFE battery is "reserved" (see my previous posting in this topic) either to protect against full discharge (which I think is a buffer of about 10% at the "bottom") or full charge (which I think is a buffer of about 5% at the "top"). Both of these buffers seem quite reasonable to me, based on what I understand about li-ion batteries, so I am not aggravated by the range performance of my FFE.

Besides, I can easily achieve the advertised range (about 76 miles), regardless of what I believe the battery capacity to be.

 

[sourcejockey]

I certainly hope that's the case--I've been trying to get Ford to do something about my battery, and if most people are seeing a 10% difference (vs. my 30%), I have a better case.

 

[Bloggin]

20% of the battery is held back for safety and battery pack longevity reasons.

The e-Golf 115mile range is based on the European driving cycle (NEDC). Which will work out to about EPA 70 miles in the US. For comparison, in Europe Nissan advertise that the Leaf gets 124 miles range(NEDC). When in the states, based on the 80% usage, it's at an EPA 75 miles. At it's very risky 100% it's at EPA 84 miles.

Note: Nissan has no issue with allowing 100% capacity use just 'warning' the consumer about battery degradation. Because they also have their $100/mo 'never ending' battery rental plan for those who damage their battery packs and lose too much capacity for it to be functional. It's a revenue generator for Nissan to allow 100% use of the battery pack. One you damage your battery, you can't drive without a battery, so the rental is the only option. Nissan Wins! Which means only a complete *%$#@ or the unwise would buy a used Nissan Leaf with that unprotected battery pack, and looming $100/mo lifetime battery rental just waiting for you.

On the other hand, Ford does not intend to profit from early battery degradation, but is focused on the consumer having the confidence of a battery with a longer life. Which is why the current 80 mile or EPA 76 mile battery, manages by software, is expected to last well over 300k miles before any capacity issues noticeable by the owner. The battery pack is designed to last longer than the actual vehicle. The Consumer Wins!

 

[WattsUp]

20% of the battery is held back for safety and battery pack longevity reasons.

I believe it is more like 15%, as mentioned in the previous postings.

The general consensus is that 19.5 kWh is the usable capacity of the FFE battery. Some people have seen this number, or something close to it, in their Trip View, after depleting the battery.

19.5 kWh is about 85% of the total 23 kWh, whereas 20% of 23 kWh would only be 18.4 kWh.

Also, 19.5 kWh / 76 miles = 256 Wh/mi which, assuming 80% charging efficiency, precisely matches the 320 Wh/mi "wall-to-wheels" efficiency specified on the FFE window sticker. It also matches my personal experience of driving along at around 256 Wh/mi average efficiency and having the car estimate around 76 miles range. All this again suggests that the usable capacity of the FFE battery is something very close to 19.5 kWh.

If we assume only an 18.4 kWh usable capacity, then we'd have to assume a charging efficiency of only 75% (which seems low) in order to come with up with the same window sticker efficiency of 320 Wh/mi.

 

[Bloggin]

20% of the battery is held back for safety and battery pack longevity reasons.

I believe it is more like 15%, as mentioned in the previous postings.

The general consensus is that 19.5 kWh is the usable capacity of the FFE battery. Some people have seen this number, or something close to it, in their Trip View, after depleting the battery.

19.5 kWh is about 85% of the total 23 kWh, whereas 20% of 23 kWh would only be 18.4 kWh.

I see...very good info.

 

[dmen]

On the other hand, Ford does not intend to profit from early battery degradation, but is focused on the consumer having the confidence of a battery with a longer life. Which is why the current 80 mile or EPA 76 mile battery, manages by software, is expected to last well over 300k miles before any capacity issues noticeable by the owner. The battery pack is designed to last longer than the actual vehicle. The Consumer Wins!

Who says the FFE battery is expected to last well over 300k miles before noticeable capacity loss?
Of course I would love this to be the case, but it seems incredibly, unrealistically optimistic. FFE's warranty covers high voltage batteries and other "unique electric components" for 8 yrs/ 100000 miles, but specifically states "The Lithium-ion battery (EV battery) will experience gradual capacity loss with time and use (similar to all lithium-ion batteries), which is considered normal wear and tear. Loss of battery capacity due to or resulting from gradual capacity loss is NOT covered under the New Vehicle Limited Warranty." I will be content if this gradual capacity loss results in at least 80% of original capacity remaining when my FFE hits 100000 miles.