Smart Car of America Forum banner
1 - 20 of 37 Posts

· Super Moderator
Joined
·
2,159 Posts
Discussion Starter · #1 ·
What is the warranty on the 12v battery in a new electric car? I thought I saw somewhere that it was 12 months, but I could not find any info about it in the warranty book. The fact that it is not mentioned leads me to believe that it would be covered by the four year/50,000 factory warranty. Anyone know for sure? I'm particularly interested in the condition of a 12v battery in a 451 that's been sitting on a dealer's lot for two or three years. My car had been sitting on a dealer lot for two years and I've had it for two more years with no issues so far.

Len
2014 EV
 

· Premium Member
Joined
·
2,298 Posts
What is the warranty on the 12v battery in a new electric car? I thought I saw somewhere that it was 12 months, but I could not find any info about it in the warranty book. The fact that it is not mentioned leads me to believe that it would be covered by the four year/50,000 factory warranty. Anyone know for sure? I'm particularly interested in the condition of a 12v battery in a 451 that's been sitting on a dealer's lot for two or three years. My car had been sitting on a dealer lot for two years and I've had it for two more years with no issues so far.

Len
2014 EV
It's not under warranty because it can be too easily sabotaged. If it works, I wouldn't worry about it until it no longer does.
 

· Registered
Joined
·
931 Posts
I know that when Steven Villatoro bought his leftover Smart ED, he had the dealer change that battery before delivery to him. When I bought my leftover 2015 ED, I asked about the state of the battery and was told it was fine, since they had driven it several times during our purchasing process (to move it from display to a reserved area, and then to and from the service bay for PDI) with no problems. So I'm hoping the long term storage didn't do it any significant damage.

How big is this battery anyway? It couldn't be that expensive. Is it like a golf cart or riding mower battery?
 

· Super Moderator
Joined
·
2,159 Posts
Discussion Starter · #4 ·
It's not under warranty because it can be too easily sabotaged. If it works, I wouldn't worry about it until it no longer does.
Thanks, but is that exclusion mentioned somewhere in the owners manual or warranty book? I didn't see it in the warranty book and the exceptions to the four year warranty are mentioned there, i.e. wipers, brakes, etc. Seems to me like anything not specifically excluded would be included. Curious.

Len
2014 EV
 

· Registered
Joined
·
1,756 Posts
If not driven/kept charged regularly any 12v battery - ICE or ED - will begin to deteriorate. I would either negotiate a new battery or be prepared to replace it. Some will luck out, others may experience failure soon.
 

· Registered
Joined
·
3,460 Posts
Warranty on a new car starts on day of first use so it should be covered if "new". I read through some of the '15 gas model warranty and it seems like it would be covered under the basic warranty like you suggest. Yes, I looked at the gasser warranty because you noted you looked at the ED warranty already. The ED accessory battery should last a very long time considering it does not have to crank a starter....
 

· Registered
Joined
·
832 Posts
Seems like the 12V battery should last longer in the ED than in an ICE car. No starter to crank. Many of the other systems should be running off the HV battery.
One would think that!

But there is an opposing argument to be made: No starter means it never gets "exercised" at all. But it still gets charged whenever the car is on. That's not good for lead-acid batteries, causes the plates to densify and looses capacity.

And since it's never used to crank a starter, you also don't notice when it's getting tired until it's quite dead.

In my Honda Insight the 12V battery never lasted more than 3-4 years for that reason. My smart is getting that old now, have to keep an eye on it.
 

· Registered
Joined
·
3,460 Posts
One would think that!

But there is an opposing argument to be made: No starter means it never gets "exercised" at all. But it still gets charged whenever the car is on. That's not good for lead-acid batteries, causes the plates to densify and looses capacity.

And since it's never used to crank a starter, you also don't notice when it's getting tired until it's quite dead.

In my Honda Insight the 12V battery never lasted more than 3-4 years for that reason. My smart is getting that old now, have to keep an eye on it.
Exercise of a lead acid battery, as you call it, causes lead to go into solution and redeposit (as it is charged), not necessarily uniformly as the designer wishes. I have batteries on maintainers for years. (I can't afford to keep all the cars insured and registered for the road at the same time.) They crank right up as soon as I wish. No issues....

(That Insight has a starter. I just checked...)
 

· Registered
Joined
·
254 Posts
With an ICE battery, you know it is failing when it struggles cranking the engine in the morning. Is there a tell-tale signal with an ED battery? Or is it just turning the key one morning and none of the electrical gauges work?
 

· Registered
Joined
·
1,612 Posts
With an ICE battery, you know it is failing when it struggles cranking the engine in the morning. Is there a tell-tale signal with an ED battery? Or is it just turning the key one morning and none of the electrical gauges work?
You turn the key and nothing comes on. I ran my battery flat once leaving the parking lights on.

However, unlike an IC engine with starter, I only had to hook a little 3A charger to the battery for a couple minutes (you'll hear some relays clicking) then the car will "start" and the remainder of charging done from the traction pack.

This means that a useful emergency item to keep in the ED might be a small sealed-lead-acid battery (or even just 10 "D" cells wired together) that you can use to jump the battery.
 

· Registered
Joined
·
254 Posts
You turn the key and nothing comes on. I ran my battery flat once leaving the parking lights on.

However, unlike an IC engine with starter, I only had to hook a little 3A charger to the battery for a couple minutes (you'll hear some relays clicking) then the car will "start" and the remainder of charging done from the traction pack.

This means that a useful emergency item to keep in the ED might be a small sealed-lead-acid battery (or even just 10 "D" cells wired together) that you can use to jump the battery.
Good tips; thanks. Just curious, how does a traction pack work? I am vaguely familiar with the way an alternator works in the ICE car, but obviously there is no alternator in an ED.
 

· Registered
Joined
·
1,612 Posts
Good tips; thanks. Just curious, how does a traction pack work? I am vaguely familiar with the way an alternator works in the ICE car, but obviously there is no alternator in an ED.
Traction pack is maybe an old term for the main battery pack that powers the motor (plus the heater and AC too). The 12 volt battery is charged by the 350 volt traction pack via a 12 volt DC-DC converter/charger. The 12V charger only operates when the car is switched on in "ready" mode.
 

· Registered
Joined
·
254 Posts
Traction pack is maybe an old term for the main battery pack that powers the motor (plus the heater and AC too). The 12 volt battery is charged by the 350 volt traction pack via a 12 volt DC-DC converter/charger. The 12V charger only operates when the car is switched on in "ready" mode.
Based on that, it would seem that the ED battery should last longer than an ICE battery because I would assume that it needs very, very little power to start the car. So unless you place a big load on it while the car is switched off (like leaving parking lights on), it should function until it effectively can't hold a charge at all (whereas an ICE battery becomes useless once it can't crank the starter, even though it still has a bit of charge left).
 

· Premium Member
Joined
·
2,298 Posts
Based on that, it would seem that the ED battery should last longer than an ICE battery because I would assume that it needs very, very little power to start the car. So unless you place a big load on it while the car is switched off (like leaving parking lights on), it should function until it effectively can't hold a charge at all (whereas an ICE battery becomes useless once it can't crank the starter, even though it still has a bit of charge left).
Based on my observations, the low voltage EV battery can be expected to last 3 to 5 years.
 

· Registered
Joined
·
832 Posts
maintainers
Yes, very different form the DC/DC converter in the smart ED. The ED keeps the battery at 14V all the time the car is on or charging. That's just terrible and leads to densification and sulfatisation. Maintainers use a lower float voltage to reduce densification and gassing, the better ones also actively pulse the battery to counter sulfatisation.

(That Insight has a starter. I just checked...)
Yes, it uses it when the HV battery is dead, or when the outside temperarture is < -20C. About a dozen times total over the 15 years I owned the car.
 
1 - 20 of 37 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top