Flat battery in less than 2 weeks

[Andy H]

Hi all,

I've previously left my car for 3+ weeks and it's started no problem. The weekend before last I drove over 200 miles so the battery should have been fully charged on my return. This morning the battery was completely dead and I had to use the manual key and then boot access. I connected my rapid boost charger and after a while I was able to lock and unlock the doors again. I'm going to keep it on charge for a few hours but it's introduced that element of doubt and worry for my weekend trip.

I'm sure I didn't leave anything on in the cabin and there are no after market accessories connected (no tracker). I don't suppose there's any way to know what caused this after the event. Has anyone else found themselves in a similar position and managed to do any analysis with a multimeter to at least prove there's a parasitic drain?

Thanks, Andy.

 

[Beachbum]

Cant help here, but I would say, once a battery has died it is never as good as it was.
If it lost charge in 2 weeks, this time round, I doubt it will last that long after the full discharge.
I would suggest using a trickle charger more frequently now and/or consider getting a new battery

 

[DJManc]

Hi all,

I've previously left my car for 3+ weeks and it's started no problem. The weekend before last I drove over 200 miles so the battery should have been fully charged on my return. This morning the battery was completely dead and I had to use the manual key and then boot access. I connected my rapid boost charger and after a while I was able to lock and unlock the doors again. I'm going to keep it on charge for a few hours but it's introduced that element of doubt and worry for my weekend trip.

I'm sure I didn't leave anything on in the cabin and there are no after market accessories connected (no tracker). I don't suppose there's any way to know what caused this after the event. Has anyone else found themselves in a similar position and managed to do any analysis with a multimeter to at least prove there's a parasitic drain?

Thanks, Andy.

I have not yet suffered from a complete drain, but if I dont use the car for a couple of weeks, the Ctek battery indicator that I have fixed up to the battery shows red that its very low and needs charge immediately. Never known this in any other car I have had before and I am convinced that there is something draining the battery!

 

[Andy H]

Cant help here, but I would say, once a battery has died it is never as good as it was.
If it lost charge in 2 weeks, this time round, I doubt it will last that long after the full discharge.
I would suggest using a trickle charger more frequently now and/or consider getting a new battery

Thanks for the answer. I think I'd feel pretty cheated if I had to replace the battery after 6 months. Even when I've had a battery run flat in the past, it's been OK after with a full charge. I'd be looking to Lotus warranty if it keeps happening.

 

[Andy H]

I have not yet suffered from a complete drain, but if I dont use the car for a couple of weeks, the Ctek battery indicator that I have fixed up to the battery shows red that its very low and needs charge immediately. Never known this in any other car I have had before and I am convinced that there is something draining the battery!

I do wonder if this has been a gradual long term decline. I have a trickle charger but I haven't been using it religiously. I guess I can just get into the habit of using it between drives.

 

[crestima]

Hi all,

I've previously left my car for 3+ weeks and it's started no problem. The weekend before last I drove over 200 miles so the battery should have been fully charged on my return. This morning the battery was completely dead and I had to use the manual key and then boot access. I connected my rapid boost charger and after a while I was able to lock and unlock the doors again. I'm going to keep it on charge for a few hours but it's introduced that element of doubt and worry for my weekend trip.

I'm sure I didn't leave anything on in the cabin and there are no after market accessories connected (no tracker). I don't suppose there's any way to know what caused this after the event. Has anyone else found themselves in a similar position and managed to do any analysis with a multimeter to at least prove there's a parasitic drain?

Thanks, Andy.

Hey Andy,
Yes, this happened to me once too with the OEM battery, and I had to go through the same ordeal to access and recharge it. There's lots of speculation, including my own, about the actual root cause of the battery drain and why it only occurs sporadically. I'm afraid I can't really shed much insight on this, but if you refer to my post of Sept. 4th on the thread "Battery Drain", you'll find out that I opted to buy an Antigravity Battery with the remote kick-start feature as a last resort. This feature really does work and has actually saved my hide once already. I can understand that not everyone is willing to shed the extra $ for the Antigravity, but if you come to the point of having to replace the OEM battery anyway, then perhaps it may make that upgrade investment a bit more sensible. Btw, the collateral weight savings is pretty significant too.

 

[gwman]

Hey Andy,
Yes, this happened to me once too with the OEM battery, and I had to go through the same ordeal to access and recharge it. There's lots of speculation, including my own, about the actual root cause of the battery drain and why it only occurs sporadically. I'm afraid I can't really shed much insight on this, but if you refer to my post of Sept. 4th on the thread "Battery Drain", you'll find out that I opted to buy an Antigravity Battery with the remote kick-start feature as a last resort. This feature really does work and has actually saved my hide once already. I can understand that not everyone is willing to shed the extra $ for the Antigravity, but if you come to the point of having to replace the OEM battery anyway, then perhaps it may make that upgrade investment a bit more sensible. Btw, the collateral weight savings is pretty significant too.

Crestima,
What size Antigravity did you get? Their site recommends a T6 but the owners manual size parameters match an H6. I have an H6 already and wondering if it will fit.

 

[crestima]

Crestima,
What size Antigravity did you get? Their site recommends a T6 but the owners manual size parameters match an H6. I have an H6 already and wondering if it will fit.

I have the Antigravity T6/L2 Lithium 40ah, which I purchased from GRP. It's dimensions are a bit smaller than the OEM battery, but it secures well with the existing bracket.

 

[Blackthought_]

The antigravity is perfect. I’ve had it on a few other cars including lotus cars and weeks later it fires right up. Also comes with a remote and saves battery to start the car in case you leave on something that drains the battery. Expensive but very worth it

 

[Andy H]

Thanks for all the tips. I'll look into the antigravity model above to see if there are UK distributors.

 

[Porter]

Did you possibly leave the car unlocked? I know when in an unlocked state the power drain is much higher on the Emira because it wakes up a ton of the internal systems in preparation to drive.

On my car at even tries to connect to the cell phone etc. Not just when I unlock the car, but if I even walk by the car hours after finishing a drive and turning the car off, if I had forgotten to lock the doors.

 

[Blackthought_]

Did you possibly leave the car unlocked? I know when in an unlocked state the power drain is much higher on the Emira because it wakes up a ton of the internal systems in preparation to drive.

On my car at even tries to connect to the cell phone etc. Not just when I unlock the car, but if I even walk by the car hours after finishing a drive and turning the car off, if I had forgotten to lock the doors.

Your car doesn’t lock automatically if you forgot to lock it? (Assuming the keys are not inside)

I used to hate working on a lotus because it used to yell at me when I unlocked the car (but did not open a door) and went to the trunk to work on something back there. I then learned just open the door and it will not lock it and not yell at me

 

[JohnS]

Hi all,

I've previously left my car for 3+ weeks and it's started no problem. The weekend before last I drove over 200 miles so the battery should have been fully charged on my return. This morning the battery was completely dead and I had to use the manual key and then boot access. I connected my rapid boost charger and after a while I was able to lock and unlock the doors again. I'm going to keep it on charge for a few hours but it's introduced that element of doubt and worry for my weekend trip.

I'm sure I didn't leave anything on in the cabin and there are no after market accessories connected (no tracker). I don't suppose there's any way to know what caused this after the event. Has anyone else found themselves in a similar position and managed to do any analysis with a multimeter to at least prove there's a parasitic drain?

Thanks, Andy.

Hello Andy,

A battery monitor may help to discover if there is a high quiescent current being drawn from you battery. If you get a battery monitor which has Bluetooth communication with your smart phone (app) you can interrogate the, battery voltage, charge and temperature by just standing near to the car.

I've found with my i4 Emira the air fans and water pumps can be operating to cool the engine for a good 1/2 hour after a long high speed journey. This can reduce the battery charge from being 100% down to ~60%. Also as stated above by others, just the opening of a door from being locked, opening the boot, closing a door without locking discharges the battery.

Short journeys of 1/2 hour doesn't put back in enough charge to replenish the battery.

A simple solution to the above problem is to, lock the car, open the boot and connect up a battery charger to recharge the battery. Close the boot lock by using a screwdriver imitating the boot being closed. This means when the battery is fully charged the charger can be disconnected without any further charge being drawn from the battery. The boot can be gently lowered onto the locked mechanism, this be opened and the boot re-locked at a later date when the car is to be driven. Using the battery monitor, the decaying battery charge can be viewed over time.

Hope this helps.

John

 

[Andy H]

Did you possibly leave the car unlocked? I know when in an unlocked state the power drain is much higher on the Emira because it wakes up a ton of the internal systems in preparation to drive.

On my car at even tries to connect to the cell phone etc. Not just when I unlock the car, but if I even walk by the car hours after finishing a drive and turning the car off, if I had forgotten to lock the doors.

This is a good shout. I honestly can't remember when I came to the car whether the mirrors we out or folded. To be honest, this would 100% explain the different behaviour and give me confidence about it not happening again.

 

[Andy H]

Many thanks to everyone who replied including the ingenious screwdriver boot lock trick! And I agree, the fans and other accessories do seem to have a mind of their own sometimes.

I keep my car garaged so I'm going to get into the habit of using the CTEK between weekends. I'll also look into the battery monitor as I love a gadget

 

[Nick Sticks]

Many thanks to everyone who replied including the ingenious screwdriver boot lock trick! And I agree, the fans and other accessories do seem to have a mind of their own sometimes.

I keep my car garaged so I'm going to get into the habit of using the CTEK between weekends. I'll also look into the battery monitor as I love a gadget

I don't understand the need for the boot lock screwdriver trick.
I close the boot on the cable with the whole car locked.
It stays on charge for the longer periods I'm not using the car with the CTEK cutting in as and when it needs to.
By the way, "my trick" is to hang something from the rear view mirror to remind yourself that there's a cable attached.

 

[Beachbum]

I don't understand the need for the boot lock screwdriver trick.
I close the boot on the cable with the whole car locked.
It stays on charge for the longer periods I'm not using the car with the CTEK cutting in as and when it needs to.
By the way, "my trick" is to hang something from the rear view mirror to remind yourself that there's a cable attached.

I put the trickle charger box on the steering wheel

 

[JohnS]

I don't understand the need for the boot lock screwdriver trick.
I close the boot on the cable with the whole car locked.
It stays on charge for the longer periods I'm not using the car with the CTEK cutting in as and when it needs to.
By the way, "my trick" is to hang something from the rear view mirror to remind yourself that there's a cable attached.

Hello Nick,

The 'boot lock screwdriver trick' is just a means being able to reverse the car out of the garage and drive away without having to perform various functions to the car. I've already damaged a wing mirror as I forgot to rotate inwards to get passed the garage door surround. As per yourself I need to have some sort of 'trick' to resolve this problem.

I'm not a fan of float charging a car battery, as I've not read any articles discussing the long term effects on the AGM battery. AGM battery charging regime is also subtly different to conventional lead-acid batteries.

The other effect of having a fully charged battery is seen by the battery monitor. The battery voltage fluctuates after starting up of the engine. I've noticed the charging system is indecisive, by this I mean, sometimes the battery voltage is allowed to decay before increasing to ~13.9V. Sometimes the battery voltage changes between ~13.9V and ~14.4V. I don't know the charging algorithms programmed into the car electronics, but its obvious that something is going on. Whether this is good or bad I don't know, I just hope whoever designed it has accounted for all of the scenarios.

I invite anyone with technical knowledge please share your research on the above two issues.

John

 

[Rupes]

Did you possibly leave the car unlocked? I know when in an unlocked state the power drain is much higher on the Emira because it wakes up a ton of the internal systems in preparation to drive.

On my car at even tries to connect to the cell phone etc. Not just when I unlock the car, but if I even walk by the car hours after finishing a drive and turning the car off, if I had forgotten to lock the doors.

That's funny, because I thought the opposite might be true. I leave mine unlocked in the garage under the assumption the alarm was causing some battery drain. I do keep the key pretty far away so it doesn't wake up the car though.

Meanwhile, my 10 year old Mazda will sit outside in all kinds of temperatures for weeks at a time and always fires up with no issues. Seems like maybe the OEM battery on the Emira just isn't up to the task.