Dell 'Primarily AC use' option missing from bios

[Kee Yong, Ting]

Hi, I've recently replaced my Dell Precision M4800 battery with a reputable third party battery. After that I realized that certain options are missing from bios under power management section, one of it is 'Primarily Ac use' option. When I reattached my original Dell battery back to the machine, these options reappeared. I'm trying to understand what trick is my Dell laptop's doing here, how & why does it manage to turn off certain feature just by swapping to third party battery.

[RAS_3885]

Detecting a non-OEM battery is pretty straightforward, so no tricks. If they can't verify the batter specs and integrity (because third party) then disabling some power options can make sense.

[Kee Yong, Ting]

Is there any way around this limitation? Like re-programming the non oem battery firmware to trick the laptop? Since Dell no longer selling those batteries (FV993). 

[RAS_3885]

No practical way. Possible? Sure, I'm sure somebody, somewhere could make it work, but the effort wouldn't be worth it.

 

What actual functionality have you lost with those BIOS settings being removed? I don't know what 'Primary AC Use' does...

[Kee Yong, Ting]

This feature allows to set the battery charging limits, so that it'll stop charging after reaching certain percentage. Else, it'll impact the battery life. In fact my laptop will keeps charging the non oem battery, even it has reached 100%, the charging led kept lit.

[BlueChinchillaEatingDorito]

9 minutes ago, RAS_3885 said:

I don't know what 'Primary AC Use' does...

• Standard - Fully charges the battery at a moderate rate. This setting provides a balanced approach to extending battery life while still providing a reasonably fast charging time. Recommended for users who frequently switch between battery and external power sources.
• ExpressCharge™ - Quickly charges the battery using Dell's fast-charge technology. Recommended for users who need the battery to charge quickly. If the system is powered off, then the battery typically charges to 80 percent within one hour and 100 percent in two hours. Charge time may be longer if the system is powered on.
• Primarily AC Use - Extends battery life by lowering the charge threshold, so that the battery never charges to 100 percent capacity. Recommended for users who primarily operate the system while plugged into an external power source.
• Adaptive - Automatically optimizes battery settings based on the user's typical patterns. Recommended for users who want to set and forget.
• Custom - User selects when the battery starts and stops charging. Recommended for advanced users.

Source: https://www.dell.com/support/kbdoc/en-ca/000123091/how-to-improve-the-performance-of-a-dell-laptop-battery

 

@Kee Yong, Tinghave you installed Dell Power Manager or Dell Command | Power Manager to see if those options are listed there? 

[RAS_3885]

3 minutes ago, Kee Yong, Ting said:

This feature allows to set the battery charging limits, so that it'll stop charging after reaching certain percentage. Else, it'll impact the battery life. In fact my laptop will keeps charging the non oem battery, even it has reached 100%, the charging led kept lit.

Even with a non-OEM battery the laptop charge controller will stop charging and enter a standby/trickle charge mode when the battery is full. It's not going to keep pumping charge into the battery. That's basic charging behavior. If you use a replacement battery so sketchy it couldn't support this the laptop would likely just give you a battery error and not allow charging at all.

[BlueChinchillaEatingDorito]

3 minutes ago, RAS_3885 said:

Even with a non-OEM battery the laptop charge controller will stop charging and enter a standby/trickle charge mode when the battery is full. It's not going to keep pumping charge into the battery. That's basic charging behavior. If you use a replacement battery so sketchy it couldn't support this the laptop would likely just give you a battery error and not allow charging at all.

Yea I wouldn't be surprised if this replacement battery is missing controllers the OEM battery would've had to report various parameters on the condition of the battery back to the laptop. 

 

40 minutes ago, Kee Yong, Ting said:

Hi, I've recently replaced my Dell Precision M4800 battery with a reputable third party battery. 

Who is this reputable third party battery manufacturer? Why not just provide their name if they're reputable? 

[Kee Yong, Ting]

48 minutes ago, BlueChinchillaEatingDorito said:

@Kee Yong, Tinghave you installed Dell Power Manager or Dell Command | Power Manager to see if those options are listed there? 

Yes, the options showed are the same as in the bios. 'Primarily AC Use' option is also missing

[Kee Yong, Ting]

47 minutes ago, BlueChinchillaEatingDorito said:

Who is this reputable third party battery manufacturer? Why not just provide their name if they're reputable? 

Bought it from BattDepot, the battery itself manufactured by Dr.Battery.
https://www.battdepot.com/uk/opn/notebook+battery/dell/fv993/lde277-ap.aspx

[Kee Yong, Ting]

56 minutes ago, RAS_3885 said:

Even with a non-OEM battery the laptop charge controller will stop charging and enter a standby/trickle charge mode when the battery is full. It's not going to keep pumping charge into the battery. That's basic charging behavior. If you use a replacement battery so sketchy it couldn't support this the laptop would likely just give you a battery error and not allow charging at all.

Wouldn't it be better if the battery stop charging at 80% or 90% instead of always staying at 100%.

[Arika]

2 hours ago, Kee Yong, Ting said:

the battery itself manufactured by Dr.Battery.

which likely means it's missing the controller required for such a limit to be put in place. Unfortunately there's not going to be much you can do about it if that's the case.

[RAS_3885]

On 2/19/2022 at 7:59 PM, Kee Yong, Ting said:

Wouldn't it be better if the battery stop charging at 80% or 90% instead of always staying at 100%.

Theoretically, yes, but I've never found a non-OEM battery that lasts as long as the OEMs did in a replacement scenario.

 

It's an 8 year old laptop... I'd just use and not worry about it. Even if it lasts only two or three years you can buy another battery, but at that point the laptop itself is going to be well beyond obsolete.