My battery died! Did that injure it ?

Things I do:

1. Turn the dome light right off. Turn off the hatch light.

2. Never just sit in the car listening to radio in accessory mode.

3. If the car's going to be sitting idle, a day or more, hook up my smart charger, let it run through the charging program, and leave it connected, as a maintainer.

4. Invest in some toys: multi meter, electronic load tester, smart charger, jump pack.

5. Read up, everything you can, on batteries, charging, replacements available.

6. Accept that batteries are a consumable, just swap it out on a schedule. Just like getting periodic dental check up: better sooner than later.

 

Might be better to say "if you don't abuse it".
Just drive it normally.

The folks that have early battery death generally are:
Those who use the car very little; like once a week for less than 10 miles.
Those who have a habit of running accessories when the car is not "ON".
Those who make a mistake and leave an accessory ON when the car is just parked. That includes an ODB scanner.

 

You know the expression "rust never sleeps"? A close second is "phantom loads never sleep". I agree, if you're low usage you really need to get a charger, a smart one that can left on indefinitely. Leave it convenient to the jump point, use it whenever the car sits multiple days. This'll save you from being "obligated" to drive the car more frequently, saves gas.

 

As someone who works on machines that run on 6v, 12v, 24v, 36v, and even 48v in rare moments, plus my 97 Jeep with a battery from 2006 and my father's 79 Ford with a battery from 1998 before it was sold, I'll tell you this... Batteries either work or they don't. You don't need some overpriced "smart" charger, you don't need a new battery if the car starts fine and is over 12.00v when off overnight. If you drain a battery to the point it can't even operate a light bulb then yes you damaged it a bit, but it will either recover after a charge or never work again. If you drain it till all the lights in and outside of your car are dim you've done no damage just jump it and drive for half an hour it'll be charged again. I'm so tired of misinformation on batteries. We've even had other service technicians who have let customers waste thousands on new battery packs because the computer labeled them "weak" when the machine hasn't had any issues.
So TL : DR... If your car still starts a week after you let it die it will still be good months, if not years, from now. Just avoid excessive high amperage (jump starting, "quick" charging, etc).

 

Good post.
Sometimes batteries (and other things really) work now and fail an hour from now.
If you want a RELIABLE battery, it is a good thing to replace it at the first sign of potential trouble.

 

You most certainly can jump a dead 12v battery. There's a special connection in the under-hood fuse box to connect the positive jumper cable to. You cannot jump start another dead conventional vehicle from your Prius, though, because the DC power inverter from the main battery to 12V is not designed to handle the load of a conventional starter.

 

If the 12V battery dies, the car can usually be jumped. If the Traction battery dies, MG1 cannot start the ICE. The car must be towed.

 

If voltage gets too low the computer will not run and the traction battery relay will open. A jump will not help you then.

 

No that's not cool.
And may not even be possible.......depending on exactly how the battery failed.
If a cell or two is shorted internally, the bad battery may drag down the whole 12 V system enough that it won't run even after jumped.
Not common maybe but possible.

And letting a battery go COMPLETELY discharged can greatly shorten it's overall life too.

 

No this is not at all true. The 12V battery only boots the computers (MCUs) NEVER start the MG (guessing you mean motor/generator) and the 12V NEVER starts the engine either ... that only start if the car is in ready on the MAIN DRIVE battery ...

So I am not really confident of the rest of your analysis either (just a hint batteries do NOT care about years/months but proper (or improper) charging cycles, and deep discharges (in case of AGM types) and operating temperatures ... so those years are highly suspect to me.... The main battery also similarlry doesn't really care miles or years.

 

Not sure what you mean? I think the "jumping" in this context mean another 12V battery attached (probably large enough capacity) that could provide enough power to keep the voltage high enough (in the same time of course the old battery is a load). This definetely can be done and was done I guess maybe a million time.

 

Jumping usually means temporarily connecting to another battery, usually in another vehicle. If the 12V battery will not hold a charge, as stated by the post I was responding to, the relay would open when the "jumping" battery was disconnected, shutting down the Prius.

 

I think you can jump start, disconnect and the car will keep running. Maybe needs to be at least borderline charge? Not sure.

 

Where exactly did you get that idea ??
Once the car "starts", the HV battery and converter produce all the 12 V you need.
Unless the 12 V battery is missing or completely shorted, it should work fine until you shut it off.

 

I do not believe this is true. the DC/DC converter is a "voltage" generator able to push close to 100 Amp... and it is there statically. All the 12V bus is powered by it almost no circumstances the voltage would drop under 12V (unless you have a real short somewhere then main fuse blows of course, even if the battery shorted there is fuse there so it will blow that first not the main one If the main fuse blows then your scenario may occur but then you have a lot bigger issue than 12V battery )

While car is in READY nothing needs the 12V battery to be even there. It doesn't matter if it holds charge or not. Have not tried but I bet you could even disconnect it. I did measure that when the Battery is full only minimal current passes through the 12 v battery.