Go Back   EcoModder Forum > EcoModding > Instrumentation
Register Now
 Register Now
 

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 07-12-2014, 01:28 AM   #11 (permalink)
EcoModding Newb
 
redpoint5's Avatar
 
Join Date: Aug 2010
Location: Oregon
Posts: 7,896

Acura TSX - '06 Acura TSX
90 day: 25.55 mpg (US)

Lafawnda - '01 Honda CBR600 F4i
90 day: 47.32 mpg (US)

Big Yeller - '98 Dodge Ram 2500 base
90 day: 21.82 mpg (US)

Prius Plug-in - '12 Toyota Prius Plug-in
90 day: 57.64 mpg (US)

Mazda CX-5 - '17 Mazda CX-5 Touring
90 day: 23.74 mpg (US)
Thanks: 2,606
Thanked 3,109 Times in 2,314 Posts
Quote:
Originally Posted by 2000mc View Post
Unfortunately this looks like it would at best save about as much as having a taillight burned out.
What I'm thinking is that this would be the same as a float charge. Battery tender has some charts putting float charge at 50-100mA
Agreed. Charging and discharging efficiency is a miniscule drop in the overall efficiency of petrol vehicles. Charge efficiency only needs to be considered in systems where they are heavily used, such as EVs, alternator deletes, and hybrid traction batteries.

Regardless, I'm curious, and I don't see much information available from internet searches. My ultimate goal is to do an alternator delete while preserving as much convenience and longevity of the battery as possible.

__________________
Gas and Electric Vehicle Cost of Ownership Calculator







Give me absolute safety, or give me death!
  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 07-12-2014, 05:52 AM   #12 (permalink)
Master EcoModder
 
sendler's Avatar
 
Join Date: May 2011
Location: Syracuse, NY USA
Posts: 2,935

Honda CBR250R FI Single - '11 Honda CBR250R
90 day: 105.14 mpg (US)

2001 Honda Insight stick - '01 Honda Insight manual
90 day: 60.68 mpg (US)

2009 Honda Fit auto - '09 Honda Fit Auto
90 day: 38.51 mpg (US)

PCX153 - '13 Honda PCX150
90 day: 104.48 mpg (US)

2015 Yamaha R3 - '15 Yamaha R3
90 day: 80.94 mpg (US)

Ninja650 - '19 Kawasaki Ninja 650
90 day: 72.57 mpg (US)
Thanks: 326
Thanked 1,312 Times in 966 Posts
Why not just test on the bench with a charger and a consumer?
  Reply With Quote
Old 07-12-2014, 06:52 PM   #13 (permalink)
EcoModding Newb
 
redpoint5's Avatar
 
Join Date: Aug 2010
Location: Oregon
Posts: 7,896

Acura TSX - '06 Acura TSX
90 day: 25.55 mpg (US)

Lafawnda - '01 Honda CBR600 F4i
90 day: 47.32 mpg (US)

Big Yeller - '98 Dodge Ram 2500 base
90 day: 21.82 mpg (US)

Prius Plug-in - '12 Toyota Prius Plug-in
90 day: 57.64 mpg (US)

Mazda CX-5 - '17 Mazda CX-5 Touring
90 day: 23.74 mpg (US)
Thanks: 2,606
Thanked 3,109 Times in 2,314 Posts
Quote:
Originally Posted by Old Tele man View Post
TRANSLATION: "consumer" = dummy "load"
I thought you were calling me a dummy load.

I brought my LiFePO4 and Supercap to work along with some resistors and meters and should be able to complete some tests. I'll start with 10% depth of discharge and then go down from there to 50% DoD and chart efficiency.
__________________
Gas and Electric Vehicle Cost of Ownership Calculator







Give me absolute safety, or give me death!
  Reply With Quote
Old 07-12-2014, 07:47 PM   #14 (permalink)
Master EcoModder
 
IamIan's Avatar
 
Join Date: Dec 2010
Location: RI
Posts: 667
Thanks: 366
Thanked 214 Times in 131 Posts
If helpful.
For A123 Flavor LiFePO4 20Ah cells.

Over a extended period of time (months) they have much much less self Discharge at any given temperature than more conventional PbA.
Link

Available discharge capacity is reduced at lower temperatures. Similar effect in PbA (but different magnitude).
Link

The complete cycle (Charge + Discharge) efficiency (Ah or Wh) reduces at higher rates (A or W).
Varying discharge rates Link

With no other changes (rate,temperature,etc) the cycle (Charge + Discharge) efficiency ( Ah or Wh ) reduces at high SoC/SoE.
Link
Link

The electrical resistance reduces at Higher SoC/SoE , but Increases at lower temperatures... Less resistance = Higher efficiency ... Agrees with above efficiency vs SoC/SoE measure.
Link

Peukert Effects of reduced Ah/Wh are almost entirely in the direction of the increased rate ... meaning if your Discharge rate increases but your charge rate does not ... less Ah/ Wh will be seen on the discharge part of the cycle ... and the opposite is also true ... if your charge rate increases but your discharge rate does not ... less Ah/Wh will be seen on the charge part of the cycle ... this effect is almost entirely on the CC portion of charge or discharge ... if a CV stage to charge or discharge is also included very little of this effect will actually be seen ... although, the time of the CV portion will greatly be effected by the CC rate portion.
  • I saw less than 1% deviation on the charge (Ah or Wh) from deviation on the discharge rate from 10A to 100A.
  • The end of CC portion moved ~5% (SoC/SoE) away from the bottom for discharge varying from 10A to 100A.
  • I saw less ~0.5% deviation on the discharge (Ah or Wh) from deviations on the charge rate from 10A to 75A.
  • the end of CC portion moved ~5% (SoC/SoE) away from the top for charge varying from 10A to 75A.

Taking what we know above combined with the OEM power vs SoC graph.
Link
We can also see a significant preference in allowable power pulses in the discharge direction ... Not just raw Watts ... but at the top SoC the Regen hits the 3.8v listed @ ~900W that's ~236Amps ... but on the opposite end the bottom discharge hits the 1.6v listed @~800W that's ~500Amps... which is also interesting considering the deviation we saw above in the resistance changes at those different ends of the SoC band.

- - - - -
I used the following:
  • 3 PowerLab8's connected together (up to 120A rates charge or discharge combined).
  • VA18B multi-Meter
  • Instek GPD-2303S Power Supply
  • 36 NiMH 6 cell Sticks from HEV Civic for high power for the PL8s.

~32MB compressed raw data from years of testing if desired

- - - - - -

Forgot to add ... these cells prefer to be kept bellow ~120F , for best life.
Link
Link

__________________
Life Long Energy Efficiency Enthusiast
2000 Honda Insight - PHEV - Solar
Electric Unicycle - Solo Wheel Glide3

Last edited by IamIan; 07-13-2014 at 05:45 AM.. Reason: remove unneccessary content
  Reply With Quote
Reply  Post New Thread


Thread Tools




Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2020, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com