Lithium Batteries for a mobile (flight safe / legal) imaging rig.

[fireballxl5]

Although my preference is for LiFePO4 batteries I've gone and bought one of these...

https://amzn.eu/d/9NJQJcl

If falls just below the 100Wh limit and seems to be super slick. It will be used to provide primary power for my Canon DSLR and tracker mount at Monday's TSE, so weight, capacity and versatility were primary considerations here. 

I'm now a fan of batteries that have PD capable USB outputs🙂

Andy

Edited April 4 by fireballxl5
Typo

[Adam J]

33 minutes ago, fireballxl5 said:

Although my preference is for LiFePO4 batteries I've gone and bought one of these...

https://amzn.eu/d/9NJQJcl

If falls just below the 100Wh limit and seems to be super slick. It will be used to provide primary power for my Canon DSLR and tracker mount at Monday's TSE, so weight, capacity and versatility were primary considerations here. 

I'm now a fan of batteries that have PD capable USB outputs🙂

Andy

how are you getting 100Wh it's described as 27000mah so only 27Wh? 

Adam

 

[fireballxl5]

1 hour ago, Adam J said:

how are you getting 100Wh it's described as 27000mah so only 27Wh? 

Your calculation is implying that current and power capacity are the same. I'm no electrical engineer but my understanding is that the relationship between power and current capacity (Wh and Ah) depends on the voltage that is driving the current. So a stated power capacity of 99.54Wh (Anker product website for this power bank) implies a cell voltage of 3.6V, i.e. power / current 99.54Wh/27.65Ah = 3.6V. . 

Happy to be corrected here🙂

[Adam J]

6 hours ago, fireballxl5 said:

Your calculation is implying that current and power capacity are the same. I'm no electrical engineer but my understanding is that the relationship between power and current capacity (Wh and Ah) depends on the voltage that is driving the current. So a stated power capacity of 99.54Wh (Anker product website for this power bank) implies a cell voltage of 3.6V, i.e. power / current 99.54Wh/27.65Ah = 3.6V. . 

Happy to be corrected here🙂

yes I actually noted 3.6volts but in my post but for some reason it's been cut short. 

[fireballxl5]

5 minutes ago, Adam J said:

yes I actually noted 3.6volts but in my post but for some reason it's been cut short. 

So you agree that it is (almost) a 100Wh capacity battery? Again,  my understanding is that the power capacity is fixed with the time that current can be drawn determined by the voltage used (and the current level of course).  This would mean that at 3.6V/1A the current rating is 27.65Ah,  whereas at 12V/1A (using a handy USB PD 12V trigger) it would be 8.3Ah.

Regards,  Andy

[Adam J]

9 minutes ago, fireballxl5 said:

So you agree that it is (almost) a 100Wh capacity battery? Again,  my understanding is that the power capacity is fixed with the time that current can be drawn determined by the voltage used (and the current level of course).  This would mean that at 3.6V/1A the current rating is 27.65Ah,  whereas at 12V/1A (using a handy USB PD 12V trigger) it would be 8.3Ah.

Regards,  Andy

Yes but it does not mention 3.6volts at any point I can see, you basically have to reverse engineer that. For me at least that does not build confidence. The only voltage it mentions at the link is 28 volts for example. 

[Elp]

On 03/04/2024 at 22:23, Adam J said:

So not sure on your battery monitor, make sure that the charger is set correctly as if its like mine it has many different options. My max charge voltage is about 14.3 - 14.4 volts on the LIFE charge profile. 

Take note of how much you put into the battery. 

Are you sure that monitor is for LIFE batteries and not Lead Acid as that would set 12.8 volts as 100% charge.

Adam 

I charged the battery up, went up to 13.4V. Tried it on my rig, the voltage quickly drops again to mid or just above 11V. Think it has to have a regulator connected up.

But for my purposes which is likely more power hungry than a "normal" setup I instead bought a Pegasus 12V 10A mains adaptor. Ran it for 30 minutes indoors with the peltiers running near 85pc and the rig didn't restart once, which is expected running off mains. So for me this is sufficient for my needs, I likely won't take this setup off site.

[Adam J]

18 minutes ago, Elp said:

I charged the battery up, went up to 13.4V. Tried it on my rig, the voltage quickly drops again to mid or just above 11V. Think it has to have a regulator connected up.

But for my purposes which is likely more power hungry than a "normal" setup I instead bought a Pegasus 12V 10A mains adaptor. Ran it for 30 minutes indoors with the peltiers running near 85pc and the rig didn't restart once, which is expected running off mains. So for me this is sufficient for my needs, I likely won't take this setup off site.

No that should not happen unless you are drawing more than 8 amps or so, as that will trigger some of the over current protection. 

[Elp]

1 minute ago, Adam J said:

No that should not happen unless you are drawing more than 8 amps or so, as that will trigger some of the over current protection. 

Around 3.5-4A it was drawing. The absolute max based on when I measured each device separately would be 6A total.

 

Edited April 5 by Elp

[Adam J]

3 minutes ago, Elp said:

Around 3.5-4A it was drawing. The absolute max based on when I measured each device separately would be 6A total.

 

In that case the voltage should not drop. Might be worth doing some more testing at lower current draw and see if it is still dropping, 

How much charge did it take according to your charger?

Adam

[Elp]

26 minutes ago, Adam J said:

How much charge did it take according to your charger?

Capacity to full? It was at 60pc when at 12.4V or so. The charger only has percentage indicators in 20's when charging to indicate battery charge, it was charging roughly at 4.5A (it's max is 5A).

Edited April 5 by Elp