Hybrid Battery Discharged Below 40% Threshold
#11
05-08-2015, 05:18 AM
Re: Hybrid Battery Discharged Below 40% Threshold
Go to Figure 1 at this web site of the DOE's AVTA ( avt.inl.gov/pdf/hev/batteryfusion4699.pdf ) to see the voltage vs. energy discharged for the 2010 FFH HVB. AT 20% discharged or 275 Whrs the cell voltage ( divide by 204 ) is 1.31. At 80% discharged, 1.096 KWhrs, the cell voltage is 1.25. This is the maximuum range the battery is operated in except when reconditioning when it goes to 0% discharged.
The voltage falls off the cliff at about 1.15 v.
The FEH has more cells but the NiMH cells probably behave similarly. When operated over this narrow voltage range it's believed that the HVBs life will exceed that of the rest of the car. The Dorman Replacement HVBs sound like a good deal.
The voltage falls off the cliff at about 1.15 v.
The FEH has more cells but the NiMH cells probably behave similarly. When operated over this narrow voltage range it's believed that the HVBs life will exceed that of the rest of the car. The Dorman Replacement HVBs sound like a good deal.
EDIT:
I now see where you get that from but I think that there is an error in that PDF. It shows 204 cells but 330V divided by 1.25V(nominal voltage) equals 264 cells not 204 cells so at that 80% it would be .96V. At 204 cells or 204x1.25V it would be only 255V not 330V. Looking at it another way, 330v divided by 204 equals 1.61V/cell an overcharged condition.
It means there is an error "somewhere" in published specs.
Found a WiKi page that stated 330V with 250 cells. Normally battery packs specs are: a 9.6V pack is 9.6 divided by 1.2 or 8 cells. Hmmm, I should have used 1.2 instead of 1.25 above!!
Last edited by wptski; 05-08-2015 at 06:10 AM.
#12
05-08-2015, 07:18 AM
Re: Hybrid Battery Discharged Below 40% Threshold
Read up further in the pdf. The FFH HVB has 204 cells and is nominally 275 V. It also has a voltage booster. I picked a HVB voltage of 235 V where the pack is discharged 1350 w-hrs to yield a cell voltage of 1.15. The curve is heading straight down there.
#13
05-08-2015, 08:16 AM
Re: Hybrid Battery Discharged Below 40% Threshold
Read this page: http://en.wikipedia.org/wiki/Ford_Escape about half way down it mentions Sanyo battery pack 330V with 250 cells.
Last edited by wptski; 05-08-2015 at 09:08 AM.
#15
05-08-2015, 12:07 PM
Re: Hybrid Battery Discharged Below 40% Threshold
Since nothing agrees on the amount of cells, one can only guess and I really wonder if Ford designed a different Ni-MH battery pack system for each.
#19
05-08-2015, 07:26 PM
Re: Hybrid Battery Discharged Below 40% Threshold
Whoops! Sorry, I misread that but why are you talking about a Fusion if it's different in a Escape forum?
#20
05-08-2015, 09:41 PM
Re: Hybrid Battery Discharged Below 40% Threshold
The theory of the cars and the NiMH HVB's are the same. I knew about the government tests on the Fusions and all the data so I was just trying to help you guys understand how they worked and the difficulties to be encountered in what the OP is attempting to do. I also remember reading somewhere that putting together a perfectly good used HVB and a perfectly good powertrain could be very difficult because of software and unit identity mismatches.
Last edited by lolder; 05-08-2015 at 09:45 PM.
