DJI smart battery to output to 12v to run other things?

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Hi All

Wondering if I can use my DJI phantom 4 smart batteries to run any other items, such as a fish finder?

Rather than buying and caring for another 12v lead acid gel cell for this purpose, I'm hoping there might be an adapter that outputs 12v to say a cigarette lighter plug? I've tried searching, but only find 12v car chargers.

Hoping someone will know?
Thanks, Rob
 
I haven’t seen a 3rd party product however it’s a simple DIY proposition- all you need is a buck converter, in line fuse holder and connectors.
 
It's not just the voltage, but also the amps you need to be concerned about. I have seen ways to get voltage out of a DJI battery to do things like charge a phone. I kind of doubt it will work for your fish finder, whatever that is. Good luck.
 
It's not just the voltage, but also the amps you need to be concerned about. I have seen ways to get voltage out of a DJI battery to do things like charge a phone. I kind of doubt it will work for your fish finder, whatever that is. Good luck.
If we consider that the phantom might fly for 18 mins on 5Ah (rough figures) that’s 16A average rating we can expect from the battery. The fish finder will probably draw 120 to 150W (including the ultrasonic transducer)- less than 12A at 12V, so it will work. Not very practical though as it would deplete the pack within 30 mins of running.
 
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Really? You buy a $1200 flying camera and want to use its battery to power a fish finder? Doesn’t your boat have a battery?
 
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Really? You buy a $1200 flying camera and want to use its battery to power a fish finder? Doesn’t your boat have a battery?
That's a very unhelpful snarky comment that sounds like it's only purpose is to maintain your membership of the sexual self sufficiency society. No the boat doesn't have a battery because it's a kayak and requires a battery source, but thanks for your 2 cents worth.
 
If we consider that the phantom might fly for 18 mins on 5Ah (rough figures) that’s 16A average rating we can expect from the battery. The fish finder will probably draw 120 to 150W (including the ultrasonic transducer)- less than 12A at 12V, so it will work. Not very practical though as it would deplete the pack within 30 mins of running.
Thanks for that. Guys run their fish finders on 12v 7ah gel cells so the current draw must be a lot less that you're guessing. Will have to look into it more. Seems like a convenient solution if I can use one of the many drone batteries I have rather than having to buy gel cells for only this occasional use.
 
Thanks for that. Guys run their fish finders on 12v 7ah gel cells so the current draw must be a lot less that you're guessing. Will have to look into it more. Seems like a convenient solution if I can use one of the many drone batteries I have rather than having to buy gel cells for only this occasional use.
I’m not surprised there are less power hungry finders- I was quoting from memory the specs of one we installed in a Mates boat- power isn’t an issue for him, he has a genset and a healthy bank of deep cycle batteries.
 
As mentioned, must know the specs. for it. 12 volts is a nominal supply A normal lead acid battery will be a bit more.

A Lowrance HDS Carbon 7 (and other Lowrance units) will run on 10.8 to 17 volts. Typically the power consumption is 1-2 amps, so you're looking at over 2 hours of run time from a P4 (5350 mAh) battery.

Your battery, IIRC, is a 4 cell, 15.2 volt (nominal) so it'll be about 16.2 volts fully charged (4 x 4.2) and go down to 13.2 volts (4 x 3.3). All you would need is a connector. No buck converter needed, if your unit can take the full charge voltage.
 
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Yes, you could do it...should you...NO!

Get a motor cycle battery, and power the fish finder from that..it's cheep and light.

The main reason you shouldn't run the fish finder from a LIPO is the discharge. You should not discharge a LIPO past %50, or past 3.80v (at rest) or you will damage the cells.... permanently. And you you will never know how much you have taken out of the LIPO because we don't have a charger that will tell you how much you put back in when charging. Other lipo charger tell you everything you need to know...ours is just plug and forget.
 
Yes, you could do it...should you...NO!

Get a motor cycle battery, and power the fish finder from that..it's cheep and light.

The main reason you shouldn't run the fish finder from a LIPO is the discharge. You should not discharge a LIPO past %50, or past 3.80v (at rest) or you will damage the cells.... permanently. And you you will never know how much you have taken out of the LIPO because we don't have a charger that will tell you how much you put back in when charging. Other lipo charger tell you everything you need to know...ours is just plug and forget.

Some of the facts here are a bit inaccurate.
As far as monitoring SOC...
there are 4 LEDs on the batt. for that.
 
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Yes, you could do it...should you...NO!

Get a motor cycle battery, and power the fish finder from that..it's cheep and light.

The main reason you shouldn't run the fish finder from a LIPO is the discharge. You should not discharge a LIPO past %50, or past 3.80v (at rest) or you will damage the cells.... permanently. And you you will never know how much you have taken out of the LIPO because we don't have a charger that will tell you how much you put back in when charging. Other lipo charger tell you everything you need to know...ours is just plug and forget.
This is just not true and I’ll leave it at that.

Op, your fine. Your idea is great!

My fish finder draws something stupid like .07 amps or something. You should be able to power your finder for days off a single charge. When it gets low, you’ll know when it’s time to charge because of the indicators on the battery.
 
Order a battery discharger, the one I have has a USB connection. From there you should be able to use a USB cord with the other end removed. I would check the wires with a meter to determine which wires where needed. Good luck and Happy Hooking.
 
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This is just not true and I’ll leave it at that.

Op, your fine. Your idea is great!

My fish finder draws something stupid like .07 amps or something. You should be able to power your finder for days off a single charge. When it gets low, you’ll know when it’s time to charge because of the indicators on the battery.

So the current draw is a measly 110 ma or 250ma (presuming at 12v) with backlight on.

Like you say, why have to buy a whole new battery and charger set for the few times I might use it. I'm sick of owning gel cell batteries and them dying and being discarded. So this seems like a sensible solution. The unit seems to accept 10-17volts input.
 
The LiPo battery pack's life is finite, too. Just sayin'.

Another option for you is to use small (6 to 10 amp-hour maybe?) deep-discharge rated SLA batteries instead of gel, and a small motorcycle battery tender unit. But it won't have nearly the energy density of LiPo packs.
 
Yes, you could do it...should you...NO!

Get a motor cycle battery, and power the fish finder from that..it's cheep and light.

The main reason you shouldn't run the fish finder from a LIPO is the discharge. You should not discharge a LIPO past %50, or past 3.80v (at rest) or you will damage the cells.... permanently. And you you will never know how much you have taken out of the LIPO because we don't have a charger that will tell you how much you put back in when charging. Other lipo charger tell you everything you need to know...ours is just plug and forget.
It’s the motorcycle battery you should be keeping above 50% DOD- LiIon can be comfortably discharged well below 50% with no significant ill effects.

The battery will auto power off before reaching critical discharge. Contrary to your belief the battery smart electronics tracks remaining capacity, estimated time to empty, and healthy parameters- better than you might hope to do with a dumb Lipo and charger.
 
So bloody simple. I had an old phantom 4 car charger that had overheated, so cut the lead off and joined the battery to the lowrance fishfinder and fired it up.

Fantastic. I have a lot of drone batteries, so now I can just take this small energy dense energy source already owned and run the fishfinder without having to create more lead acid battery waste for the planet. At 110ma draw, that's possibly 4 long days fishing on one charge.

Thanks all
 

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