The BXT-99R-390 is a Standard Car Battery

[murphy]

I have confirmed that the BXT-99R-390 battery is NOT an AGM battery.

 

Sorry if I misled anyone with my misguided belief that the BXT-99R-390 was an AGM battery.

I pulled the battery out of my car and shook it.  I could hear the electrolyte sloshing around inside.  
I hooked it up to my 12 volt battery charger.  The initial reading was 56% SOC.  After a minute or so it jumped to 66% and then continued to climb in 1% increments.  The car was charged with the 240 volt charger yesterday evening.  So in about 12 hours it dropped to around 60% SOC with the car sitting idle in the garage.

I decided to put a Bosch BXT-96R-590 in the car.  This battery was purchased new in January.  That required removing the battery tray and cutting the rear end out of the tray so the battery would slide down into the tray.  That job is complete.  The first thing I noticed was that the power ports did not turn off as soon as I opened the car door.  They have always turned off immediately on opening the door with the little battery.  The second thing I noticed was the voltage did not go to 14.4 volts when the car was put in run mode.

 

The big battery will stay for a while but I would like to eventually replace it with an AGM battery.  It will be easier to find one now that I have room for a 96R size battery.

It's very disappointing that Ford chose to stick a small starter battery in the car instead of an AGM battery.  They must not have let the car sit for several days during their testing.
 

 

See post #5 in this thread for instructions to change the 12 volt battery.

Edited September 2, 2013 at 01:46 PM by murphy

[Andre07]

Thank you for taking the time to confirm what we have been suspecting for a few weeks now, that the 12 Battery being used on the Ford Hybrids is just an under powered Standard Lead Battery.

 

I agree totally, that it is very disappointing that Ford did not use an AGM Battery, and with a higher Amp Hour Rating.

 

I have been looking around locally for an AGM Battery with the dimensions you had posted in another thread but so far no luck.

 

Only AGM Batteries I have seen so far are from Motor Master in Canada.  They are rated at 700-800 A but are Group 78/34.  I will keep looking since nothing is coming up with Google Searches as of yet.

 

Optima and Odyssy Batteries are availabe in the USA but cannot find any of these in Canada.

 

Sears and Kmart in the USA, handle Diehard AGM Batteries, so I will be dropping by the Sears Canada and other stores this week to see what they may be carrying and what the Batteries are rated at..

 

Can you please post the dimensions of the BXT-96R Battery  and what type of Posts they have?

 

I will report back if I should happen to find a AGM Battery that may fit

 

Thanks again for the great work you are doing on this Site to help out all our Members.  It is very much appreciated.

Edited September 3, 2013 at 08:00 AM by Andre07

[murphy]

This table lists the sizes of most of the BCI Group codes.

 

http://www.batteryweb.com/bci.cfm

[Russael]

Thanks for the chart.  I simply plugged the dimensions in to Google and it only gave me 1 result after various attempts:

 

http://www.myhypermart.com/uk/shop.php?c=Automotive&n=248878031&i=B0032O6J5G&x=Yuasa_Professional_063_Car_Battery

 

It must be a brand new battery type and/or something that's extremely rare.  I can find some AGM batteries however most of those are smaller physically than what's there, or a little too large.  So far, only 1 dimension fits for AGMs (6.9" wide).  I tried various searches such as 8.2 x 6.9 x 6.9, 8.20 x 6.90 x 6.90, 8.2" x 6.9" x 6.9", and 8.20" x 6.90" x 6.90".  This also includes doing very specific searching such as enclosing those dimensions in quotes, such as "8.2 x 6.9 x 6.9".  Nada.

[murphy]

If you try to replicate what I did, don't blame me if it doesn't work for you.  You assume all responsibility for the modification to your car.

 
I just did it for the second time today.  This time I got a better fit.

I had a Bosch BXT-96R-590 battery that I bought in January before I knew the car existed.
It must be an "R" battery so the positive post is at the front of the car.

I did it "hot" with another battery connected to the terminals under the hood.

It is absolutely essential to completely insulate the positive battery cable, once it is removed from the old battery, to prevent it from touching any metal.
 

If you are not comfortable working "hot" don't do it hot.

 
Some functions of the car will have to be reprogrammed and the computer will have to relearn the ICE operating parameters if not done hot.

 
Empty out the trunk so nothing is in your way.

Remove the floor covering.
There are two plastic pins in the plastic piece that runs across the back edge of the trunk.  Pop both of them out.
Pull straight up on the plastic piece and note the spring clips that hold it in place.  Put it aside.
Unscrew the plastic knob at the left bottom of the trunk.  I assume it is the lower attachment for a cargo net.
Unscrew the plastic piece at the upper left.  It may be a cargo net knob or it it may be a simple piece of plastic.
Remove the battery door.
Find and remove the plastic pin that secures the battery area fiber panel to the upper left side of the trunk.
Push forward on the fiber to lift it off the two bolts that the plastic knobs were on.
Fold the fiber section toward the front of the car to reveal the battery.
Remove the bolt that secures the battery wedge in place.
All bolts and nuts in this area are metric sizes.
Unplug the vent tube from the battery.
Loosen the negative battery cable and remove it from the battery post.
Lay it on the floor of the trunk.

In the following step be absolutely certain that the wrench does not touch any metal parts of the car.

Loosen the positive battery cable and remove it from the battery post.
If you are working hot, insulate the battery cable so no part of the connector is visible.
I wrapped it with copious amounts of cloth.
Remove the nut that secures the two ends of the battery strap together and separate them.
Lift the battery out of the car.
Move the vent plug from the front of the old battery to the front of the new battery.
The battery tray is held by three bolts.
I removed the battery tray from the car and cut the rear end out of it.  Two short vertical cuts and one long horizontal cut.
The new battery now fits snugly into the tray.  Test the fit before putting the tray back into the car.
Bolt the modified tray into the car and install the battery.
Connect the positive battery cable to the battery.
Connect the negative battery cable to the battery.
If working hot, disconnect the auxiliary battery.
It is not possible to use the bolted wedge clamp to hold the battery.
The strap that bolts together around the battery fits fine.
Plug the existing vent tube into the rear vent of the new battery.
Put the fiber wall and the plastic trim back in place.

If this sounds complicated get help or don't try it.
 

Edited September 2, 2013 at 01:48 PM by murphy

[Andre07]

Thanks for the chart.  I simply plugged the dimensions in to Google and it only gave me 1 result after various attempts:

 

http://www.myhypermart.com/uk/shop.php?c=Automotive&n=248878031&i=B0032O6J5G&x=Yuasa_Professional_063_Car_Battery

 

It must be a brand new battery type and/or something that's extremely rare.  I can find some AGM batteries however most of those are smaller physically than what's there, or a little too large.  So far, only 1 dimension fits for AGMs (6.9" wide).  I tried various searches such as 8.2 x 6.9 x 6.9, 8.20 x 6.90 x 6.90, 8.2" x 6.9" x 6.9", and 8.20" x 6.90" x 6.90".  This also includes doing very specific searching such as enclosing those dimensions in quotes, such as "8.2 x 6.9 x 6.9".  Nada.

This is very interesting and worthy of taking note

 

The Battery you linked above, the YAB063

 

as is displayed on the site:

 

Features:

• 12V
• 45Ah
• 380CCA
• Sealed Calcium
• 3 Years Warranty

 

Now although this may or may not be very similar to the BXT-390R-390

 

the YAB063 indicates that it is rated 380 CCA but is  rated at only 45Ah.   Meaning that it can deliver 45 Amps for 1 hr then the  SOC may go so low that it is not usable

 

The BXT-99R-390 appears to have a CCA rating of 390, by the Model Name, so I wonder what the Ah rating is.  I have a feeling it may be well under 300Ahs or so many ppl would not be reporting so many issues.

 

As murphy has stated that after after removing the L2 charger and the 12V battery was fully charged that not 12 hours later the 12 Volt Battery had a SOC of only 60% with only the Computer, perhaps the "Call Home" running and calling as it pleases.

 

I wonder how long the BXT-99R-390 would be able to sustain an 11V rating with a Load of say 45 Amps.  This would be a good test to determine the Ah rating of this small Battery.  Hopefully murphy will have a chance to run this test with say a 45 Amp Load  (266 mΩ resistor) since he has a Voltage Plotting Meter.  (Hint...Hint...murphy)

Edited September 3, 2013 at 08:01 AM by Andre07

[murphy]

I wonder how long the BXT-99R-390 would be able to sustain an 11V rating with a Load of say 45 Amps.  This would be a good test to determine the Ah rating of this small Battery.  Hopefully murphy will have a chance to run this test with say a 45 Amp Load  (266 kΩ resistor) since he has a Voltage Plotting Meter.  (Hint...Hint...murphy)

Your math is wrong.  A 45 amp load at 12 volts would require a 0.26667 ohm resistor rated at 540 watts.

 

I have a battery load tester that applies a 100 amp load for 10 seconds.  To pass the battery voltage must remain above 11 volts for the entire 10 seconds.  I don't know how close to 100 amps it is since I have no way to measure 100 amps.  It uses a coil of wire that gets red hot in 10 seconds.  Going much longer than 10 seconds would probably destroy the tester.

 

This is it:

 

http://www.amazon.com/Actron-CP7612-Battery-Load-Tester/dp/B0009XQUJI/ref=sr_1_4?ie=UTF8&qid=1378146853&sr=8-4&keywords=battery+load+tester

 

 

Somewhere on either this forum or the Hybrid forum I posted a decay plot with a 15 ohm  10 watt load.

If I can find it I'll add a link to this post.

 

I found it.

 

http://www.fordfusionenergiforum.com/topic/1190-bxt-99r-390-battery-discharge-plot/?do=findComment&comment=6268

Edited September 2, 2013 at 06:43 PM by murphy

[Andre07]

Your math is wrong.  A 45 amp load at 12 volts would require a 0.26667 ohm resistor rated at 540 watts.

 

I was using 12.6 Volts, being the value of a Fully charge Battery.

 

For determining the State of Charge of a Battery all Battery Manufacturers use Ah, Amp Hours, I believe.

 

For 12 Volts then V=I.R  so R=Volts/Amps   R =12V/45Amp= 0.2666 Amps

 

If a Battery is rated at 45Ah  then it should draw 45 Amps for approximately 1 hour or less which is the Reserve Capacity

 

using 12V then yes Watts = I.E = 45 A  x 12 V = 540 watts which would be the Resister Power Rating required so that it does not glow red a Higher Wattage would be safest.

 

Batteries are all rated by Amp hours and this is why I was asking that we try a test using a lower valued Restor so we can get a higher Current Draw.  Hard to do the test properly without knowing how much Current the Car uses when it is Shut down and idle.  If Ford had used a Battery with the Ah rating marked we would not have to go thru all this.

 

I have a battery load tester that applies a 100 amp load for 10 seconds.  To pass the battery voltage must remain above 11 volts for the entire 10 seconds.  I don't know how close to 100 amps it is since I have no way to measure 100 amps.  It uses a coil of wire that gets red hot in 10 seconds.  Going much longer than 10 seconds would probably destroy the tester.

 

I am familiar with the Tester and the test. 

 

It is a Current Cracking test  to see how much of a Voltage drop occurs after 10 Seconds to simulate the current delivered to the Starter  but it does not Measure the true Capacity of a Battery..

 

To figure out the Resister being used, try pressing the Test Switch and with a Multi Meter on the Ohms Scale you can mease the Resistor being used.

 

So for a 12 Volt Battery reading 12V  the Resistor would be around  R=Volts/Current = 12V/100A = 0.12 Ohms

 

 

This is it:

 

http://www.amazon.com/Actron-CP7612-Battery-Load-Tester/dp/B0009XQUJI/ref=sr_1_4?ie=UTF8&qid=1378146853&sr=8-4&keywords=battery+load+tester

 

I have a similar Tester but on mine I have 2 Positions, one like yours to do a CCA  Test for 10 Seconds with a 100+ Amp draw and yes the Coiled Wire gets Red hHt, but on mine I have another Position on the switch which causes a 50 Draw and I keep it going for 2 Minutes before that coil gets Hot..

 

I also have a DC Amp Probe at my Disposal

 

What I do not have is a Ford Fusion Energi nor Hybrid nor a BXT-99R-390 Battery to do the tests myself

 

Somewhere on either this forum or the Hybrid forum I posted a decay plot with a 15 ohm  10 watt load.

If I can find it I'll add a link to this post.

 

I found it.

 

http://www.fordfusionenergiforum.com/topic/1190-bxt-99r-390-battery-discharge-plot/?do=findComment&comment=6268

 

Yes I did see the Graph which was nicely done thank you

 

From your Voltage/Time Graph it shows that for the 1st 2 hours it dropped 0.4 Volts from 12.2 to 11.8 Volts which is quite a steep discharge rate then tapers out to dropping about  .02 Volts in 2 Hours when using a 15 ohm resistor which works out to I=V/R=12V / 15 Ohm = 0.8 Amps

 

This is why I was asking that a lower Value Resister be used to simulate a 45 Amp Draw to see what Voltage the Battery would show after 1 Hour.  If it drops to 8 Volts or less in 1 Hour then the Battery would be rated at around 45 Ah.

 

Please understand that I am not questioning you but adding to your current findings so far, just hoping we can figure out what the Battery is really Rated at in Amp Hours

Edited September 3, 2013 at 08:06 AM by Andre07

[larryh]

From the murphy's plot, the initial current was about 12.2/15 = 0.81 A and the final current was about 11/15 = 0.77 A.  The average current over the plot was about 0.77A.  The amount of charge drawn was then approximately 0.77 A * 28.4 H = 22 Ah.  The voltage dropped about 2 V during this time period.  So over another 28.4 H, it might drop another 2 V to less than 9 V.  The average current during this time period would be approximately 0.66 A.  So that would be another 0.66 A * 28.4 H = 19 Ah.  So I am guessing the rating is more than 22 + 19 =  41 Ah if you are measuring down to 8 V.

Edited September 2, 2013 at 10:32 PM by larryh

[murphy]

 

This is why I was asking that a lower Value Resister be used to simulate a 45 Amp Draw to see what Voltage the Battery would show after 1 Hour.  If it drops to 8 Volts or less in 1 Hour then the Battery would be rated at around 45 Ah.

A resistor capable of putting a 45 amp load on a battery is way beyond anything to which I have access.

[Andre07]

A resistor capable of putting a 45 amp load on a battery is way beyond anything to which I have access.

Sorry, I forgot to suggest trying a Stove ring Element or a Stove Baking Element if you had any laying around.  I recall using both when I was doing some testing and if memory serves me correctly they had a resistance of around 0.250 ohms and they did not turn red hot cause it is only a 12 Volt Source they just got very warm to the Touch.  I clamped it to a Table Vice for my tests. (that was over 30 years ago!!!!!!)

 

It was just a suggestion to see how the BXT-99R-390 display the Volt/time Graph when drawing a Higher Current cause I believe the rate of Discharge would be steeper than it was with the 15 Ohm Resistor.

 

A 5 or 10 Amp draw should also work, just that it would take Longer to bring the Battery to a SOC to 0% which would be around 8 V. (actually at 1.2 volts/cell or 7.2V) a Battery is considered Dead.

 

But realistically I believe any Voltage below 11V would render the Battery Useless on the Car as it may be too low to energize any relays.

 

I did a bit more research and most Hybrid Manufacturers are using Batteries with a Reserve Capacity of 45 to 50 Amp.

 

Since these Batteries are used solely for Lighting, Fans, Computers and Screen Monitors they do not need too high a Current Rating but should be large enough so that the Battery does not go dead with regular use.

 

Most of these Batteries being used are rated at CCA of 550 to 600 A at 0'F and  500 to 550A at 32'F, but the Reserve Capacity ranged from 40 Ah to 45Ah

 

Most of the ones I checked have a Reserve Capacity rating of 7.5 - 8.0% of the CCA.

 

So if the BXT-99R-390 follows the same ratio than I would think that this battery would have a Reserve Capacity of (390A * 8.0%) no more than 32Ah with a fully charged battery with a SOC of 100% or 12.6V.

 

Another way to determine the Capacity of a fully charged Battery is by using the Ah rating divided by 20 Hours

 

For the BXT-99R-390 which if we assume to be rated at 390 Ah, and we are not 100% certain of this yet it would been that this battery could deliver up to 19.5A for 20 hours (390 / 20)  But we do not know what the rating is and can only assume it is 390 Ah from the Model

 

Hopefully if the BXT-96R-590 Battery indicate the Ah and the Reserve Capacity then we could get a better handle on the BXT-99R-390

 

Is there a Reserve Capacity value imprinted on the BXT-96R-590 Label by chance?

 

If yes would it be around 45 Ah or 50Ah?

Edited September 3, 2013 at 09:20 AM by Andre07

[Andre07]

From the murphy's plot, the initial current was about 12.2/15 = 0.81 A and the final current was about 11/15 = 0.77 A.  The average current over the plot was about 0.77A.  The amount of charge drawn was then approximately 0.77 A * 28.4 H = 22 Ah.  The voltage dropped about 2 V during this time period.  So over another 28.4 H, it might drop another 2 V to less than 9 V.  The average current during this time period would be approximately 0.66 A.  So that would be another 0.66 A * 28.4 H = 19 Ah.  So I am guessing the rating is more than 22 + 19 =  41 Ah if you are measuring down to 8 V.

Not sure that any relays can be energized with a Voltage under 11.0V

 

I believe someone has mentioned that the Computer places the 12 Battery into Preservation Mode around that Voltage.

 

So if 11.0 volts and higher is the value that the Battery is functional then the Currrent draw in the 28 hours of murphy's graph using a 15 ohm resistor the total current that was drawn would have been 21.735 Amps.  

 

 

Trying to post this Graph:.  Hope it works, If it needs fixing up I will do it tomorrow, getting late.

 

 

                           

Using a 15 Ohm resistor as a constant Load                            

                           

Time    Voltage  Load  Current  Watts       Amp/

Interval .............Ohms...............................2 hrs

     

0.0       12.20      15    0.813    183.000           

31        12.150    15    0.810    182.250           

61        12.050    15    0.803    180.750           

91        11.950    15    0.797    179.250           

121      11.850    15    0.790    177.750    2.007       

151      11.800    15    0.787    177.000           

181      11.750    15    0.783    176.250           

211      11.700    15    0.780    175.500           

241      11.680    15    0.779    175.200    1.564       

271      11.670    15    0.778    175.050           

301      11.660    15    0.777    174.900           

331      11.650    15    0.777    174.750           

361      11.640    15    0.776    174.600    1.554       

391      11.630    15    0.775    174.450           

421      11.620    15    0.775    174.300           

451      11.600    15    0.773    174.000           

481      11.580    15    0.772    173.700    1.548       

511      11.570    15    0.771    173.550           

541      11.550    15    0.770    173.250           

571      11.530    15    0.769    172.950           

601      11.520    15    0.768    172.800    1.539       

631      11.500    15    0.767    172.500           

661      11.490    15    0.766    172.350           

691      11.470    15    0.765    172.050           

721      11.460    15    0.764    171.900    1.531       

751      11.450    15    0.763    171.750           

781      11.430    15    0.762    171.450           

811      11.415    15    0.761    171.225           

841      11.400    15    0.760    171.000    1.523       

871      11.400    15    0.760    171.000           

901      11.390    15    0.759    170.850           

931      11.380    15    0.759    170.700           

961      11.370    15    0.758    170.550    1.518       

991      11.360    15    0.757    170.400           

1021    11.350    15    0.757    170.250           

1051    11.340    15    0.756    170.100           

1081    11.330    15    0.755    169.950    1.513       

1111    11.315    15    0.754    169.725           

1141    11.300    15    0.753    169.500           

1171    11.275    15    0.752    169.125           

1201    11.260    15    0.751    168.900    1.505       

1231    11.250    15    0.750    168.750           

1261    11.225    15    0.748    168.375           

1291    11.125    15    0.742    166.875           

1321    11.200    15    0.747    168.000    1.493       

1351    11.190    15    0.746    167.850           

1381    11.185    15    0.746    167.775           

1411    11.175    15    0.745    167.625           

1441    11.160    15    0.744    167.400    1.490       

1471    11.150    15    0.743    167.250           

1501    11.100    15    0.740    166.500           

1531    11.085    15    0.739    166.275           

1561    11.075    15    0.738    166.125    1.480       

1591    11.050    15    0.737    165.750           

1621    11.000    15    0.733    165.000    1.470       

          

27 Hrs     ..............  Avg 0.806 A .................  21.735 Ah  in 27 hours   

 

Edited September 3, 2013 at 09:56 AM by Andre07

[murphy]

Here are the specs for the Bosch BXT-96R-590 battery.

 

Bosch Premium Performance Battery Group Size 96R
Part # 96R590B   SKU: 9929951

Group Size                                               96R
BCI #                                                        96R
Voltage                                                      12
Wet or Dry                                                Wet
Terminal Type                                           T
Right Or Left Hand Positive                     Right
Cold Cranking Amps (CCA) @ 0F          590
Cranking Amps @ 32F                             710
Reserve Capacity (minutes)                      95
Height (in.)                                                6.93
Height (mm)                                              176.0
Width (in.)                                                 6.93
Width (mm)                                               176.0
Length (in.)                                                9.49
Length (mm)                                              241.0
Weight (lbs)                                               33.0
 

 

Reserve Capacity is defined as the number of minutes the battery will last with a 25 amp load.

Edited September 3, 2013 at 10:01 AM by murphy

[Andre07]

Thanks murphy

 

Sorry but Is the Reserve Capacity (minutes)    95  Amps or Minutes?

 

Ok read your edit.

 

Understood

 

Thos BXT-96R-590  Reserve Capaticity is rate at being able to deliver 25Amps for 95 Minutes

 

So compared to other batteries

 

Capacity 700A / 20 hours = 56 Ah  .

 

This means that the BXT-99R-390 must have a lot lower Reserve Capacity and Cranking Amps, as you discovered when you replace the Battery.

 

We are getting closer to getting actual values for the BXT-99R-390....... which are way lower that the 96R-590

Edited September 3, 2013 at 10:23 AM by Andre07

[murphy]

Here is an update on the "big" 12 volt battery.

The 12 volt battery was fully charged when installed into the car.
Two days later, with the car not being driven, the 12 volt battery was at 60% SOC.
I made two 3 mile trips with a 1/2 hour stop in between.
That brought the 12 volt battery up to 90% SOC.

The power ports do not turn off immediately when the door is opened.
They stay on for between 75 and 90 minutes before they shut off.
That never happened with the small battery.
 

[murphy]

Update:

 

It has been two weeks since I put the "big" battery into the car.

There have been no battery saver messages and the power ports continue to be on for over an hour when I park the car.

:)

[murphy]

Three weeks on the "big" battery.

No problems.

 

 

The "little" battery, which is sitting on the garage floor, has not lost any of it's charge so it wasn't a self discharge problem.

[murphy]

Another update:

 

It has been 6 weeks since I put the "big" battery into the car.

There have been no battery saver messages and the power ports continue to stay powered for over an hour when the car is turned off.

With the little battery the power ports turned off the instant the driver's door was opened.

[Russael]

Very good.  How many amp hours was that original battery rated at?  Were you able to determine that?  And how many Ah do you think the 590 battery has?

 

Something that has caught my interest is a direct lead acid replacement, Lithium Iron batteries.  They're about 1/3 the weight and can be used as starter batteries for small motors, such as lawn tractors or motorcycles.  They have good cold cranking amps but seem to have a decently high Ah rating.  The descriptions of that type of battery say that they can be used with established Lead Acid chargers, so long as they don't have a desulfate mode.  They make them for computer UPSes as well as other things.  They also state that these are far more stable, safe, and tolerant in comparison to Lithium Ion batteries.

 

Only real disadvantage that I see with them is their initial cost, however, they also tout that they have a 10 year life expectancy.

[murphy]

The specs for the big battery are in post 13.

Apparently car batteries are no longer rated in AH.  There is a new spec called Reserve Capacity.  The definition is in post 13.

 

Ford doesn't publish any specs for their battery so I have no idea what its ratings are.

[Russael]

Hmmm.  Well, the Lithium Iron Phosphate batteries are physically smaller than even the 390 battery, but seem to offer 500 CCA (useless for this application, granted), and only weighs 5lbs.  Issue is the 319 dollar pricetag.  If my 12v battery gives me issues, I may consider this:  http://www.batterystuff.com/batteries/shorai-lithium-lfx36l3-bs12.html

Edited October 15, 2013 at 01:17 PM by Russael

[mmmhmmmm]

I've read this topic and thought about how to address the wimpy BXT-99R-390.

 

I found this deep cycle 99R-series. It's lead acid, but sounds like a brute.  

http://www.powerstridebattery.com/car-batteries-light-truck-batteries-van-batteries/bci-group-99r-odyssey-pc1200mjt-battery

 

I considered the Shorai, but their FAQ->Cold Weather Performance Expectations don't give me a warm fuzzy. I'm not sold on it for the Energi, although these are excellent motorcycle batteries.

http://shoraipower.com/faq

 

In the end I ordered the D35 Optima Yellow Top from Amazon and plan to modify the battery tray (see post 5).  I've used one in our Escape Hybrid for years without a problem. Every once in a while the price gets down to ~$135 on Amazon...unfortunately not the case right now.

http://www.amazon.com/dp/B000MSDKMA?_encoding=UTF8&psc=1&s=automotive#productDetails

 

I'll try the wimpy little Motorcraft BXT-99R-390 in the lawn mower come Spring. If it fits thank you Ford for the lawn mower battery.

[mmmhmmmm]

Turns out the wimpy Motorcraft BXT-99R-390 won't fit in my lawn mower. Does anybody want it? Local pickup only! I recycled it.

 

I installed the Optima Yellow Top D35 mentioned in post 22 tonight using roughly the same procedure in post 5. I did the 'hot' install by using jumper cables to sustain the Energi and wrapped the live positive lead with copious cloth as recommended. That worked well and being careful paid off.

 

Final notes:

The Optima D35  almost fits in the battery tray, but still requires the back of the tray cut off. The Optima battery lacks a lip to lock into the front of the tray. The battery does have a large lip on each corner due to the curved shape of the cells. You might drill through this and bolt the battery to the tray to hold the front down. I put a bolt into the factory hole at the rear of the tray to keep the battery from sliding backwards, and fastened the strap over the top. The factory strap fits loosely over this battery; I had to drill a hole in the strap for a tighter fit. It's not going anywhere.

 

I've never had the battery problems experienced by many here, and this should ensure against that.

 

Thanks for the heads up!

Edited February 23, 2014 at 09:00 PM by mmmhmmmm

[mmmhmmmm]

I had the trunk area back apart and got a few photos of the Optima Yellow Top D35. I haven't had a single problem with this battery. Time will tell - there are now 2 subs in the deck with an old school Rockford Fosgate Punch 100i amplifier consuming lots of power. That will definitely use the 12V battery.

 

 

 

[larryh]

The following plot shows the voltage of the 12 V battery when the car is started, but not charging the 12 V battery (that is not supposed to happen, but occurs because of an apparent software error when the car is plugged into a charger and the charger is turned off or not plugged in).  At 9 Volts, MFM issued the notification that the 12 V battery is low.  I didn't notice that the battery was not being charged until the voltage reached 6 V and things started to shut down. 

 

Edited February 7, 2014 at 04:33 PM by larryh