12v battery maintenance, issues, etc.

[dash]

@PeteChat
Under the passenger (or driver’s seat) both fine
What update are you referring to?

[r44flyer]

1 hour ago, moggio53 said:

I use one of these - is it any good? I just leave it connected when the car is in the drive - your opinion v welcome.

It's a trickle charger, reviews are OK, like anything you get what you pay for - but it's really all you need.
My only concern with any of these gadgets is that they are left alone for very long periods, in variable conditions and you hope if they fail, they fail safe.

[Heidfirst]

6 hours ago, Cyker said:

Do they really??!  

I was about to reply very few manufacturers use them as they cost 4-5x as much as a normal lead acid battery, and with cars that have a cost target they'd never do it.

Usually it only gets used by manufacturers who are desperate to save weight, so higher end performance cars and EVs mostly.

You can buy lithium 12v batteries that are drop in replacements but you'd be looking at £300-400 rather than the £70-80 for our one...!

 

oops, in my haste whilst skimming the forum I think that I missed the 12V bit ... 😳 Apols.

Unfortunately, timed out from being able to edit the original post.

[PeteChat]

10 hours ago, dash said:

@PeteChat
Under the passenger (or driver’s seat) both fine
What update are you referring to?

DCM module update (whatever that is - I assume a charging control module)

[hind]

DCM is for communication between the car and toyota servers. Also used for emergency calling IIRC

[HarryW2024]

17 hours ago, Cyker said:

Do they really??!  

I was about to reply very few manufacturers use them as they cost 4-5x as much as a normal lead acid battery, and with cars that have a cost target they'd never do it.

Usually it only gets used by manufacturers who are desperate to save weight, so higher end performance cars and EVs mostly.

You can buy lithium 12v batteries that are drop in replacements but you'd be looking at £300-400 rather than the £70-80 for our one...!

 

I suspect the real cost difference is a lot closer than that, you can get 100ah lifepo4 from around £200 retail today, ergo I’d suspect it’ll be nearer £100 vs £20 for a major like Toyota. (Shirley they’ve already saved enough money on the lack of noise suppression in the YC 😂).

also you can’t just drop one in, assuming you can find one small enough to fit, the DC/DC algorithm would need to be changed too.
Worth noting the BYD has sleep protection modes and only requires 15m of ‘ready’ mode to fully charge it too. ..

[PeteChat]

Using the BYD for comparison doesn’t work with me I’m afraid, as all the things I buy that are made in China (nearly everything nowadays 🙄) are very variable in quality. They either work first time and last well or are absolute crap - even the same item from the same supplier 😡

The same reason I would never buy an MG since the name was sold to the Chinese.

[HarryW2024]

Ok fair enough, the point I was making was that 12v Auxiliary LFP batteries are out there and if adopted then Toyota would clear 90% of its current gripes.

worth noting that Toyota have technical agreements and collaborations directly with BYD, so I wouldn’t necessarily and readily put them in the box marked Chinese junk. Even Tesla use their LFP blade batteries….

[PeteChat]

I, too, am not knocking ALL Chinese products, but until they respect international patents and stop flooding markets with cheap knock offs I will be cautious in what I buy.

There is a long held belief that China plays the long game. They will undercut all a county’s domestic products to cripple the local companies, then step in to buy them cheap. That means they now control that country’s market and the prices can go up. Sound familiar?

[hind]

1 hour ago, HarryW2024 said:

if adopted then Toyota would clear 90% of its current gripes.

And see some angry reviews about the price of the 12v Battery replacement, questions about their safety etc 😛 you can never please everybody. I'm certain that tuning the charging algorithm and sticking to Yuasa would be more than enough to solve the issue. 

[Mushu84]

Hi all

 

I had a volt meter (plug in the lighter kind), that I used a long time ago on an older car (works ok)

Wednesday morning put the key on on before the ready mode it was showing 11.8V, it started without issues

Thursday (today) - key on auxiliary 12.1V, Key on before ready mode 11.7V, car started ok 

Both times after start car shows 14.4V going down after drive to 14.1-14.3 depending on accessories that are on

 

Not sure if this values are ok, do I need to change the Battery? I would like to know what is normal as I am confused, I don't want to change it if there is no real issue or is normal, car works fine, no errors or issues 

[r44flyer]

3 minutes ago, Mushu84 said:

I had a volt meter (plug in the lighter kind), that I used a long time ago on an older car (works ok)

Wednesday morning put the key on on before the ready mode it was showing 11.8V, it started without issues

Thursday (today) - key on auxiliary 12.1V, Key on before ready mode 11.7V, car started ok 

Both times after start car shows 14.4V going down after drive to 14.1-14.3 depending on accessories that are on

Not sure if this values are ok, do I need to change the battery? I would like to know what is normal as I am confused, I don't want to change it if there is no real issue or is normal, car works fine, no errors or issues 

If you are not experiencing poor or non starting then leave it alone for now.

[Cyker]

16 hours ago, Heidfirst said:

oops, in my haste whilst skimming the forum I think that I missed the 12V bit ... 😳 Apols.

Unfortunately, timed out from being able to edit the original post.

Ahh phew, that makes sense, although that would have been cool if they had started doing that  

Apparently in some other manufacturers hybrids the 12v Battery is 'virtual' and is actually a fenced off portion of the traction battery; I'm interested to see what problems that potentially causes but it might be a possible way forward.

That said, the cars I've seen that have that have normal starter motors or are PHEVs, so might not work for the Toyota HSD as that requires high voltage power to start the ICE whereas those other cars can be jump started the traditional way.

5 hours ago, HarryW2024 said:

I suspect the real cost difference is a lot closer than that, you can get 100ah lifepo4 from around £200 retail today, ergo I’d suspect it’ll be nearer £100 vs £20 for a major like Toyota. (Shirley they’ve already saved enough money on the lack of noise suppression in the YC 😂).

also you can’t just drop one in, assuming you can find one small enough to fit, the DC/DC algorithm would need to be changed too.
Worth noting the BYD has sleep protection modes and only requires 15m of ‘ready’ mode to fully charge it too. ..

Straight LFP cells definitely would, but I'm talking about drop-in replacement 12v lithium car batteries - They are made to be drop-in replacement so they have more circuitry to emulate a 12v Battery so it can be charged like one, and the big high-end ones even have a supercapacitor bank to start trucks, but all this extra management circuitry plus the higher component costs and niche market is partly why they cost so much.

 

[Paul john]

17 minutes ago, Cyker said:

Ahh phew, that makes sense, although that would have been cool if they had started doing that  

Apparently in some other manufacturers hybrids the 12v battery is 'virtual' and is actually a fenced off portion of the traction battery; I'm interested to see what problems that potentially causes but it might be a possible way forward.

That said, the cars I've seen that have that have normal starter motors or are PHEVs, so might not work for the Toyota HSD as that requires high voltage power to start the ICE whereas those other cars can be jump started the traditional way.

Straight LFP cells definitely would, but I'm talking about drop-in replacement 12v lithium car batteries - They are made to be drop-in replacement so they have more circuitry to emulate a 12v battery so it can be charged like one, and the big high-end ones even have a supercapacitor bank to start trucks, but all this extra management circuitry plus the higher component costs and niche market is partly why they cost so much.

 

Virtual batteries sounds like an “all your eggs in one basket” senario… potentially problematic methinks

[Cyker]

Yeah, I suspect that's why Toyota didn't do it because, as we know, if you drain the traction Battery you're up that odorous waterway everyone talks about without a propulsion implement.

I think it might work okay with PHEVs and EVs as they have much bigger traction batteries so you'd have to be extremely negligent to drain that, but they really need to find a way to make EVs and PHEVs take power from the charger to power the 12v system, so if the car is dead you can plug in the charger and it'll supply enough base power to bootstrap the rest of the car.

 

 

 

[hind]

Powering up the HV circuit requires some check ups to complete. The whole system is designed to disconnect it if something is not right. That means that you still retain ecall, hazard lights, most of the car systems (especially the safety ones like airbags), basically enough to let you get off the road safely if something bad happens. If you power everything from the traction Battery you either accept that it will be still powering up everything when it fails (meaning that any potential short circuit is still there, glowing red) or you get total shutdown, eg. when driving downhill on the motorway at night. That's why that low voltage circuit is required to be powered up separately. 

Of course it might be the supercapacitor or separate LiFePO4 Battery or AGM or regular flooded lead acid Battery but there has to be other source of power

[Cowgirl]

2 hours ago, Mushu84 said:

Hi all

 

I had a volt meter (plug in the lighter kind), that I used a long time ago on an older car (works ok)

Wednesday morning put the key on on before the ready mode it was showing 11.8V, it started without issues

Thursday (today) - key on auxiliary 12.1V, Key on before ready mode 11.7V, car started ok 

Both times after start car shows 14.4V going down after drive to 14.1-14.3 depending on accessories that are on

 

Not sure if this values are ok, do I need to change the battery? I would like to know what is normal as I am confused, I don't want to change it if there is no real issue or is normal, car works fine, no errors or issues 

I have a volt meter like yours, my starting in aux is normally between 11.0 and 12.0. I have never seen a value above 12.0. Key on before ready as low as 10.8V!

I use a solar panel during the day while at work as I do 15 minute journeys. So far (touch wood) it has never failed to start.

I think you have to learn what’s normal for your car but I do get nervous with the low figures and go for a longer drive.

[dash]

25 minutes ago, Cowgirl said:

I have a volt meter like yours, my starting in aux is normally between 11.0 and 12.0. I have never seen a value above 12.0. Key on before ready as low as 10.8V!

I use a solar panel during the day while at work as I do 15 minute journeys. So far (touch wood) it has never failed to start.

I think you have to learn what’s normal for your car but I do get nervous with the low figures and go for a longer drive.

Your car’s resting voltage is likely nearer/above 12V. Problem is that as soon as you open the car the voltage drops due to the locks having been operated and interior lights coming on (also a few of the car’s 27 ECUs come to life), then when you turn the key to Acc position the voltage drops further as more ECUs and the radio come to life. Using a bluetooth Battery monitor I’ve seen my voltage drop 1V before getting to actually start the car.

[CPN]

4 hours ago, Mushu84 said:

Not sure if this values are ok, do I need to change the battery?

No.

4 hours ago, Mushu84 said:

I would like to know what is normal as I am confused, I don't want to change it if there is no real issue or is normal, car works fine, no errors or issues 

I've seen mine come on at 11.3v and dip to 10.7v on occasion (start pressed) after it's been left a few days and it has still started fine. My Blue Demon was new in April this year...

[Derek.w]

5 hours ago, Mushu84 said:

Hi all

 

I had a volt meter (plug in the lighter kind), that I used a long time ago on an older car (works ok)

Wednesday morning put the key on on before the ready mode it was showing 11.8V, it started without issues

Thursday (today) - key on auxiliary 12.1V, Key on before ready mode 11.7V, car started ok 

Both times after start car shows 14.4V going down after drive to 14.1-14.3 depending on accessories that are on

 

Not sure if this values are ok, do I need to change the battery? I would like to know what is normal as I am confused, I don't want to change it if there is no real issue or is normal, car works fine, no errors or issues 

I have no problems with your values and often see 11.7 volts drop when starting but just for a few seconds.

I prefer to keep my Battery voltage at 12.2 or 12.3 volts before sticking it on charge those readings are before opening or unlocking doors using a BM monitor so I can check it state when in the house.

[BlueMike1972]

Thinking of adding a plug-in voltmeter to my ubiknal- as there are so many available on places like Amazon etc, is there a particular one that any of you fine folk recommend? 

[dash]

Go for a bluetooth BM6 (which you attach to the Battery terminals). You can then monitor resting voltage properly.
See my post 4th above this one for reason.

[Derek.w]

BM6 is a newer version I am using a BM2 Battery monitor.

I also have a plug in lighter or auxilary socket kind and a multimeter for other electrical stuff.

[r44flyer]

22 minutes ago, dash said:

Go for a Bluetooth BM6 (which you attach to the battery terminals).

If you are bothered about privacy then don't buy BM2 or BM6 modules (all made in China).
You have to give the app permissions I would not recommend.
Even worse I doubt they can be trusted about the data they are harvesting in the background from your device.

[CPN]

11 minutes ago, r44flyer said:

Even worse I doubt they can be trusted about the data they are harvesting in the background from your device.

There are many ways to prevent harvesting from your devices with the right application.