Empulse Charging

[GeorgeS]

The Empulse specs say the 8.0 will recharge in 1.5 hours. This implies an approximate 4.3 Kw charger,---bigger than both the Volt and Leaf's 3.3 kw charger. Do we have any info from Brammo on the details of the charger?? I've heard it will take a standard L2, 220V charger conforming to SAE 1772.

Anybody got some details??

Thx,
GSB

[Phantom]

Here are the latest Battery/Charging specs from the Brammo website.

Empulse Batteries
Battery Type BRAMMO Lithium-Ion Battery BRAMMO Lithium-Ion Battery BRAMMO Lithium-Ion Battery
Battery Pack Capacity: 8kWh   
Battery Pack Voltage:  88.8V Recharge Time:  Level 2 = 1.5 hours 110v = approx 10 hours

I think it is 1.5 hours per 110v for a total of 10 hours for a complete charge.

[Brammofan]

I read that as -- if you have Level 2 charger, then the 8.0 will charge in 1.5 hours.  If all you have is 110v wall socket, then the 8.0 will charge in 10 hours.  Given that the Enertia has a bit over a 3.1 kWh battery pack and it takes almost 4 hours to recharge a depleted battery, that sounds about right to me.

[GeorgeS]

Brammofan, Phanton,
I read it like Brammofan ie level 2=1.5 hrs. So it's back to my original question. Does this bike really have a 4.3 kw charger?? Shoot the Volt and Leaf are only 3.3 kw. I hope Brammo really does have a 4.3 kw charger but I'm skeptical.

[Phantom]

I think level 2 charging will take 5 hours, as level 2 is twice as good as 110v.

In the unveiling video, Craig takes questions on charging about 4 1/2 minutes in.

Here is the link:

[BrammoBrian]

George and all,

Let me (hopefully) clear up some confusion regarding charging on the Empulse.  It turns out to be slightly more complex than the story that's made it into the press (this is common as media prefers simple "sound bytes" of information).

The Empulse will feature an on-board Level 1 charger derived largely from the Enertia on-board charger.  Final specifications are not yet settled, but you can expect a power delivery to the battery pack of roughly 850-1000W.  This is pretty much the maximum that can be pulled from a 110V household 15A circuit leaving enough headroom not to pop the breaker.  At this charge rate, it is roughly 1 - 1.25 hours per kWh of battery capacity to charge.

The Empulse will be configured to accept input from a Level 2 off-board charger that would be purchased separately and kept in your garage or other charging location.  As Level 2 chargers are far too large (at the moment) to fit onto a motorcycle, this is a necessary compromise.  This does also mean that you would NOT be able to charge off Level 2 charging stations that simply provide 220V/30A from the "standard" SAE J1772 charge plug as that voltage and current need to be converted to battery bus voltage and the current regulated.  This does mean that you could install a Level 2 charge station for your Empulse in your home with relatively minimal cost. A dryer outlet (220V single phase) and our off-board charger (basically a current regulating power supply) would be all that's required.

Another important point to note is that our goal with the Empulse is to provide enough range that charge time is not nearly the constraint that it is with the current Enertia.  If the bike can give you everything you need for a day's use and then some, do you care how long it takes to charge so long as it's ready to go the next morning?  Discuss...

I hope this clears up some of the confusion. 

[GeorgeS]

Thanks for the input Brian,

I will have a driving cycle which will require me to get a quick jump at my destination in order to make it home at a reasonable speed, so I am extremely interested in getting a fast charge at my destination which of course implies a fairly high power 220 charging unit. So 2 more questions:

1) What is the power level of the offboard 220 charger and
2) what is the ball park price since I will need 2 of them, 1 for home and one for my destination/turn around point.

PS I don't want to call your charger an L2 charger since that implies a J1772 plug and an ONBOARD charger---that's why I just refer to it as the Empulse 220V offboard charger,

Thx for the input.

Now can you give us any heads up on the start of production??

[protomech]

Another important point to note is that our goal with the Empulse is to provide enough range that charge time is not nearly the constraint that it is with the current Enertia.  If the bike can give you everything you need for a day's use and then some, do you care how long it takes to charge so long as it's ready to go the next morning?

Most of the time, no. The minute it takes to plug in and unplug in the morning is the true time cost of recharging, versus 5-10 minutes spent filling up my commuter bike every 160 miles.

Occasionally I would want to extend the range via recharging during downtime while away from home, which is when charging speed does come into play. Level 1 charging is 8-10 miles of charge per hour, which ranges from quite useful (recharging at work), questionably useful (charging while visiting a friend or eating a meal, watching a movie) to not useful at all (charging at a midpoint of a long trip). Faster charge speeds would help in the questionably useful situations, but only an improvement of orders of magnitude would be useful for long trips in an EV.

[BrammoBrian]

George,

Good points and great questions.  I just double checked the specifications listed on the Empulse page and realized that the "Level 2" charge time is not correct.  It is being updated as we speak.  I also concur that Level 2 charging should be called something else to avoid future confusion.  There will definitely not be a J1772 plug on the bike.

The maximum power that we would expect to see from an appropriate off-board charger would be about 2.5kW as the charge voltage will be just north of 100VDC and the charger would likely output around 25A.  This would equate to 220V charge times of (roughly):

Empulse 6.0 = 2.4 hours
Empulse 8.0 = 3.2 hours
Empulse 10.0 = 4.0 hours   

Great thing we have such dilligent, fact checking Empulse enthusiasts!  I apologize for the confusion as it was mostly my error in communicating specifications to the marketing team.  As I get more firm information on the off-board charger, I will be certain to update the members of this forum. I cannot provide a cost estimate at this moment, unfortunately.

[GeorgeS]

Thx for the input,
Just as a suggestion, maybe you guys could add a high performance charger to the accessory line and charge($) accordingly. The charger you are suggesting will add miles at a rate of about 0.5 miles/ minute. Three times that rate would be great--then we could put it on a 30 amp circuit and #10 wire (roughly).

[oobflyer]

Maybe this adapter would fit in a backpack :-)

http://www.tucsonev.com/

[Brammofan]

You have to admit, the guy saw an opportunity, and he addressed it. 

[oobflyer]

Do we know which type of plug will come with the 240V off-board charger? I see there are several different types. For example the dryer outlet in my garage is the 14-50R.

http://www.nooutage.com/nema_configurations.htm

[protomech]

George,

Good points and great questions.  I just double checked the specifications listed on the Empulse page and realized that the "Level 2" charge time is not correct.  It is being updated as we speak.  I also concur that Level 2 charging should be called something else to avoid future confusion.  There will definitely not be a J1772 plug on the bike.

The maximum power that we would expect to see from an appropriate off-board charger would be about 2.5kW as the charge voltage will be just north of 100VDC and the charger would likely output around 25A.  This would equate to 220V charge times of (roughly):

Empulse 6.0 = 2.4 hours
Empulse 8.0 = 3.2 hours
Empulse 10.0 = 4.0 hours   

Great thing we have such dilligent, fact checking Empulse enthusiasts!  I apologize for the confusion as it was mostly my error in communicating specifications to the marketing team.  As I get more firm information on the off-board charger, I will be certain to update the members of this forum. I cannot provide a cost estimate at this moment, unfortunately.

Rumbling. I'm still hopeful we'll see an update to the 'no J1772' thing : )

Some interesting tidbits:
http://www.brammo.com/empulse_specifications/ -- lists only level 1 charge times - possibly level 2 is in flux?
http://www.brammo.com/blogs/general/charge-up-in-less-than-an-hour/ -- brammo posts about a Siemens CP700A fast AC charger .. capable of 22 kw three phase, or 3.7 kw single phase charging. It'd be somewhat unfortunate if the fastest charge rate the Empulse and Enertia Plus could accept would be a ~1kw 120v/15a charge..

[Richard230]

On the other hand, 1kW would be twice the charger than I have in my GPR-S. For me, I could live with a 120 V charging system, since my house doesn't have 220, as I use natural gas for heat, cooking and drying.