PDA

View Full Version : Trying to understand battery range, Help Me



storx
04 December 2014, 1659
So i am very new to understanding EV and their parts, but i am learning as i go.. i was wanting to know if i am doing this math correctly?? because it seems to me that the calculator on the website may be wrong..

Im looking at the Nissan Leaf batteries because i have read about a handful of builds recommending them as of lately.. so i went over and looked at these..60a/h rated - 7.6V - 500 W/h - max continuous power 1875W or 240A Peak current 540A units (http://www.hybridautocenter.com/HAC4/index.php?option=com_hikashop&ctrl=product&task=show&cid=3&name=nissan-leaf-battery-module-model-2012-new&Itemid=605) for $119 each

Since i am looking to run a motor at 72 volts, i was looking at the calculations for 10 of them to get the 76 volt pack...

10 x 7.6v units for 76 volts, 600a/h, and 5,000w/h for $1,190

According to the calculator listed on this website i found, it says this for the range.. is this correct? its saying 456 mile range
6113

Nuts & Volts
04 December 2014, 1809
10 modules would only make it a 76V 60Ah pack. You add voltages when you put batteries in series and add capacity (Ah) when you put cells in parallel

brianjmajor
04 December 2014, 1823
to build upon nuts and volts' reply that'll give you a 4500 Wh or 4.5kWh battery pack (multiply 76V x 60Ah). Energy consumption rule of thumb for a motorcycle is 120-130 Wh per mile @ 40-50 mph...youre looking at a range of 30-40 miles (divide 4500Wh by 120 Wh per mile). all scientific wild a.. guesses though. The units of energy, power, volts, capacity are confusing. It doesnt help that the esteemed purveyor of these fine cells specs units in a/h.

Stevo
04 December 2014, 1848
The ad sais, at your responsibility, they can be reconfigured. Has anyone tried changing these from 2s2p to 4s? I might be able to use these afterall, if I reconfigure them.

storx
04 December 2014, 2036
10 modules would only make it a 76V 60Ah pack. You add voltages when you put batteries in series and add capacity (Ah) when you put cells in parallel

Thank you for explaining that to me, i knew it didn't seem correct as i was scratching my head going NO WAY!!!

storx
04 December 2014, 2037
to build upon nuts and volts' reply that'll give you a 4500 Wh or 4.5kWh battery pack (multiply 76V x 60Ah). Energy consumption rule of thumb for a motorcycle is 120-130 Wh per mile @ 40-50 mph...youre looking at a range of 30-40 miles (divide 4500Wh by 120 Wh per mile). all scientific wild a.. guesses though. The units of energy, power, volts, capacity are confusing. It doesnt help that the esteemed purveyor of these fine cells specs units in a/h.

Thank you for that peace of info, what is the going Wh per mile for bikes around 70mph may i ask?

Spoonman
05 December 2014, 0302
Thank you for that peace of info, what is the going Wh per mile for bikes around 70mph may i ask?

depends on the efficiency of your drivetrain, the aerodynamics of your bike, and the terrain.
120Wh/mile is suggested above, which is perfectly reasonable for an unfaired bike on an average efficiency drivetrain on a flat road with no headwind.
My own is about 160Wh/mile at that speed but it's quite upright and doesn't have a particularly efficient drivetrain.

Nuts & Volts
05 December 2014, 1042
36mile trip into work at 70 to 75mph for 25miles of the trip I'm at 122Wh/mile on a 60degF day. Basically takes me 10kW to go 75mph in a partial tuck on my R6 conversion

Stamen
05 December 2014, 1132
Kyle is that with full fairings or just the front headlight fairing?

Nuts & Volts
05 December 2014, 1342
See attached. Add a tank bag with me tucked. Driving through rolling hills on the turnpike.