Expanding expensive Blackvue Power Magic Ultra Battery (B-124X) with cheap LiFePO4 battery

[bbking30]

Hi All,

Due to the fact that the BlackVue Power Magic Expansion Battery (B-124E) is quite expensive in relation to it's capacity, I was wondering if it should be possible to expand the Power Magic Ultra Battery B-124X witch a cheap LiFePO4 Battery with 80Ah and 12.8V. For example with this model.

In theory the B-124X does not know what expansion pack it is connected to as the connection is a simle Plus/Minus cable. So I would not see any way how the B-124X could say no to a 3rd party vendor battery other than the fact it would have a different voltage). However, I'm not sure if the internal charge controller of the B-124X has a limit which it puts to the expansion port (such as max. 5 B-124E expansion packs which would add up to 33 Ah). Or would I overwhelm the B-124X in any other way with this hughe 80Ah capactiy battery?

Can anyone advise?

Thanks,

Julian

 

[Ralph2]

I too am looking for a cheap alternative to the expensive option. I only need/want a battery that would last a couple of hours. Supplied from an ACC source to keep it charged and let it run down while in park mode.
Any links to such a battery would be appreciated.

 

[StrayCam]

I too am looking for a cheap alternative to the expensive option. I only need/want a battery that would last a couple of hours. Supplied from an ACC source to keep it charged and let it run down while in park mode.
Any links to such a battery would be appreciated.

Have you tried using the Power Magic Pro yet. In many cases, that's all you would need.

 

[bbking30]

Unfortunately the car battery does not have enough capacity to serve a blackvue camera in most of the cases for longer than 24 hours. Especially modern cars with an intelligent generator and battery management system do not allow the camera to take away too much energy from the main battery. I meanwhile decided to use a battery booster (kind of a device which loads a battery from another battery). With this setup I should have quicker charging rates than putting the hughe 3rd party 80Ah LiFePo4 battery behind a Power Magic Ultra Battery B-124X. This would only charge the expansion battery with 9 amps which would mean the 3rd party battery would likely never get fully charged.

 

[StrayCam]

Unfortunately the car battery does not have enough capacity to serve a blackvue camera in most of the cases for longer than 24 hours. Especially modern cars with an intelligent generator and battery management system do not allow the camera to take away too much energy from the main battery. I meanwhile decided to use a battery booster (kind of a device which loads a battery from another battery). With this setup I should have quicker charging rates than putting the hughe 3rd party 80Ah LiFePo4 battery behind a Power Magic Ultra Battery B-124X. This would only charge the expansion battery with 9 amps which would mean the 3rd party battery would likely never get fully charged.

You're definitely right in that being parked for over 24 hours probably will just get to the Power Magic Pro range.

Plus, if you're already using a battery, it makes sense to consider the least expensive route to extend the battery range.

I drive less than 1 hour a day, and during parking, use the Power Magic Pro with great results (no external batteries). Everyone needs to figure out what works best in their situation for sure.

Good luck finding the best solution!

 

[md70Yesh]

However, I'm not sure if the internal charge controller of the B-124X has a limit which it puts to the expansion port (such as max. 5 B-124E expansion packs which would add up to 33 Ah).

As Tomcat reported in his post here, he was able to connect a 100Ah battery to his B-124X and B-124E without issues.

Or would I overwhelm the B-124X in any other way with this hughe 80Ah capactiy battery?

If I understand it correctly, by plugging in a comparable battery (12V LFP with arbitrary capacity) to the expansion slot, it is connected in parallel to the main battery and they will be drained/charged proportionally such that their voltage remains the same. However, just to be on the safe side I would do the following:

a) Equalize the batteries before they are connected, making sure they have the same voltage within 0.1V tolerance.
b) Use a voltage regulator that came with your dash cam and set it to the lowest parameter (typically 11.8V or 12V) which corresponds to 5-10% capacity. This should prevent the batteries (especially if they are not new) from complete depletion in case the BMS fails.
c) Insert a 20A fuse between the batteries, just in case there is a sudden unexpected surge or if you forget to equalize them (especially if you are charging them at home frequently).

 

[joe384]

I have used a 18Ah Roypow LifePo4 battery as a cellink extension battery without issues. I got a short piece of xt60 cable and crimped on some connectors for the battery. So I had 24Ah in total.

I can't remember exactly how much I got out of it but it was very close to my calculations based on Wh capacity and the power usage of the dashcam.