What Happens if Your High Voltage Battery is Dead?

[rivermaverick]

The recent post by a chap whose Mav wouldn’t start after been stuck in the body shop for months waiting for parts got me thinking about what happens if the HV battery is dead.

The HV battery is charged by the ICE and that is started with the HV battery.

First thought how to start the ICE – pull start it with a rope round the front damper or a starting handle through the right front wheel arch (don’t laugh – I’m old enough to remember starting handles).

More sensibly BEVs and PHEVs have an onboard charger so can you get, or do Ford dealers have, a charger to charge HV batteries?

A quick Google search came up with a company called Prolong (https://hybridautomotive.com/) that make a series of chargers for HV hybrid batteries, not cheap but cheaper and a new battery. Their cheapest one is designed to give just enough charge to start the ICE.

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[TheWizziard]

Sounds like tow truck time.

 

[jeffrol48197]

Dealers have special chargers for HV batteries...

 

[rivermaverick]

Sounds like tow truck time.

Perhaps you could tow it to the top of a hill and see if you can get enough regen braking to charge the battery and start the engine.

 

[Saltwater Cowboys]

Perhaps you could tow it to the top of a hill and see if you can get enough regen braking to charge the battery and start the engine.

Or skip the hill and flat tow it.

Another similar question I have about HV battery life: They are supposed to go 200k miles or whatever, but that could vary by a lot. How do you know when the HV battery is approaching its end of life? I assume your fuel economy and performance would start going down. At that point the cost of replacing the battery is probably more than the vehicle is worth.

 

[inthecabin]

Or skip the hill and flat tow it.

Another similar question I have about HV battery life: They are supposed to go 200k miles or whatever, but that could vary by a lot. How do you know when the HV battery is approaching its end of life? I assume your fuel economy and performance would start going down. At that point the cost of replacing the battery is probably more than the vehicle is worth.

The batteries are small compared to full EV. The battery price I read somewhere is around $2500.00.

 

[19mustang65]

Not something the average driver needs to worry about until the warranty expires and you are over 100k miles. For most people that will be 8 to 10 years and these things will be worth $5k by then.

 

[SimplyCosmic]

It's kind of fascinating to watch videos from Prius owners on rebuilding their batteries.

 

[Saltwater Cowboys]

Not something the average driver needs to worry about until the warranty expires and you are over 100k miles. For most people that will be 8 to 10 years and these things will be worth $5k by then.

Right, but I'm the kind of guy who drives their vehicles until they die. Just curious when would you know it's time to replace the battery?

 

[bbhaag]

Right, but I'm the kind of guy who drives their vehicles until they die. Just curious when would you know it's time to replace the battery?

Not sure if it's the same on the hybrid Maverick but on my Mach-E I use a combination of CarScanner: https://www.carscanner.info/ and OBDLinkMX+:https://www.obdlink.com/products/obdlink-mxp/
to track the SOH of my HVB.

 

[GPSMan]

Perhaps you could tow it to the top of a hill and see if you can get enough regen braking to charge the battery and start the engine.

Sorry. No. Not possible.

You need a healthy HV battery to turn on just about everything. Including regenerative braking.

 

[GPSMan]

Or skip the hill and flat tow it.

Another similar question I have about HV battery life: They are supposed to go 200k miles or whatever, but that could vary by a lot. How do you know when the HV battery is approaching its end of life? I assume your fuel economy and performance would start going down. At that point the cost of replacing the battery is probably more than the vehicle is worth.

Ya. Once again, not possible.

The good news; well less bad news is, you'll only need enough juice to start the engine. Even a very weak / aged battery is going to keep you on the road.

There can be defects. But without defects, they will last the life of the vehicle.

Word of caution: The WORST thing you can do is go long periods without using the truck. This is for any hybrid. Sitting unused harms the HV battery life more than anything.

Consider it can sit unused for 16 weeks when new. Subtract 1 week of idle time for each year of age.

At 15 years old you'd better be starting and running the truck at least one time per week.

You won't know health without an aftermarket scanner.

 

[rivermaverick]

Sorry. No. Not possible.

You need a healthy HV battery to turn on just about everything. Including regenerative braking.

I thought the 12 volt battery powered everything up but the HV battery cranks the engine.

 

[rivermaverick]

Word of caution: The WORST thing you can do is go long periods without using the truck. This is for any hybrid. Sitting unused harms the HV battery life more than anything.

Consider it can sit unused for 16 weeks when new. Subtract 1 week of idle time for each year of age.

At 15 years old you'd better be starting and running the truck at least one time per week.

You won't know health without an aftermarket scanner.

 

[rivermaverick]

Ford recommend starting the engine every 15 days, excerpt from the owners handbook regarding 'Storing Your Vehicle':

Start the engine every 15 days for a
minimum of 15 minutes. Run at fast
idle with the climate controls set to
defrost until the engine reaches normal
operating temperature.
• With your foot on the brake, shift
through all the gears while the engine is running.

Looks like general information not specific to the hybrid.

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