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Battery discharger unit

not sure why you think you need this... The battery will do that by itself, within a few days, safely.

Unless you need to do this faster for some reason, your truly wasting your money.
 
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The Hanatora is definitely available in the US. Maybe you have a buddy here who can buy it and ship it to you?
 
not sure why you think you need this... The battery will do that by itself, within a few days, safely.

Unless you need to do this faster for some reason, your truly wasting your money.
This unit is amazing and well worth the cost. It will charge 4 batteries at the same time saving you a lot of time, shows the voltage of each battery and let you discharge and put the battery at storage voltage at any time.
After every flight your battery is depleted, if you are going to use it again shortly you'll charge to the max but if you want to storage just charge till storage capacity without having to charge to the max and wait for the battery to discharge itself.
Another use is for topping the battery to 100%. As you said DJI smart battery starts to discharge itself after a few days but it won't let you charge again if its capacity is at 95% or more. When I need a battery at full but it is at 96% I just discharge it to 94% and charge it again to 100%, that way I can start my flight with the battery at full capacity.
 
@Faster, If all that was what the OP was looking for, I wouldn't argue.

If, as he stated, he was looking for some way simply discharge to storage levels, I stand by my opinion that it's a waste of money to purchase something for that purpose, as the batteries do it automatically.

There is nothing of substance to be gained by discharging sooner than the self-discharge, despite what some here thinking they're meaningfully improving cycle life or preserving capacity.

In fact, IMO you're reducing long-term capacity more with your topping off practice. There's a very good reason the smart battery won't let charge @95%, and that reason doesn't go away at 94%. But what do I know about this stuff? ;)

BTW, that Hanatora charger is awesome, I have the model for my A2S batteries.
 
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@Faster, If all that was what the OP was looking for, I wouldn't argue.
I though he was looking at this unit, has been widely used it before but just the OP could actually say.
If, as he stated, he was looking for some way simply discharge to storage levels, I stand by my opinion that it's a waste of money to purchase something for that purpose, as the batteries do it automatically.

There is nothing of substance to be gained by discharging sooner than the self-discharge, despite what some here thinking they're meaningfully improving cycle life or preserving capacity.
Agree with you 100% but going directly to storage capacity save time.
In fact, IMO you're reducing long-term capacity more with your topping off practice, but what do I know about this stuff? ;)

BTW, that Hanatora charger is awesome, I have the model for my A2S batteries.
Could you please elaborate here?
 
I though he was looking at this unit, has been widely used it before but just the OP could actually say.

Agree with you 100% but going directly to storage capacity save time.

Could you please elaborate here?
Sure.

LiIon batteries operate by transferring Lithium atoms back and forth across a semi-permiable membrane between two electrodes that, not too far off as an analogy, absorb the atoms like a sponge. When it gets full, Lithium metal will start to crystallize instead of being incorporated into the electrode, and tiny metal projections start to grow.

As this occurs, that Lithium is lost as charge transport, and therefore the ability to store energy. Hence capacity declines.

Eventually, these little strands grow enough from both electrodes to reach the separating membrane, and short out the cell, ending its life.

This problem occurs at the extremes – Fully charged, fully discharged. This is why LiIon batteries are stored at 50%, and why the BEST practice, ironically, is not to charge fully, nor discharge fully.

Given my understanding, I'd leave a few minutes flight on the table, rather than stress the cells with another charging cycle.
 
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I'd add that with the enormous mountain of B.S. that's piled up here about battery maintenance, the most useful advice in extending cycle life and preserving capacity is this: Don't fully charge your batteries!

Unfortunately, we have no real control over this. I'd like a charger where I can deliberately charge to, say, 97%, then stop.

However, I suspect DJI has already accounted for this in the Intelligent Battery design, as they've been refining these modules for quite some time, so I don't worry about it.
 
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Sure.

LiIon batteries operate by transferring Lithium atoms back and forth across a semi-permiable membrane between two electrodes that, not too far off as an analogy, absorb the atoms like a sponge. When it gets full, Lithium metal will start to crystallize instead of being incorporated into the electrode, and tiny metal projections start to grow.

As this occurs, that Lithium is lost as charge transport, and therefore the ability to store energy. Hence capacity declines.

Eventually, these little strands grow enough from both electrodes to reach the separating membrane, and short out the cell, ending its life.

This problem occurs at the extremes – Fully charged, fully discharged. This is why LiIon batteries are stored at 50%, and why the BEST practice, ironically, is not to charge fully, nor discharge fully.

Given my understanding, I'd leave a few minutes flight on the table, rather than stress the cells with another charging cycle.
Thanks for the explanation. I'm used to control my batteries charging on all other my RC toys with the RC charging units that let you control the charging process. I always have treated batteries as consumables, I prefer a couple minutes of flight time against a couple of charging cycles more of battery life. My RC speed cars need the best lipo batteries with a good C rating and a good capacity with excellent connectors and cap packs. Voltage dropping when amps draw is your enemy #1. In our drones getting to 97% as you said could be a sweat spot given the fact that I don't need that speed.
 
Thanks for the explanation. I'm used to control my batteries charging on all other my RC toys with the RC charging units that let you control the charging process. I always have treated batteries as consumables, I prefer a couple minutes of flight time against a couple of charging cycles more of battery life. My RC speed cars need the best lipo batteries with a good C rating and a good capacity with excellent connectors and cap packs. Voltage dropping when amps draw is your enemy #1. In our drones getting to 97% as you said could be a sweat spot given the fact that I don't need that speed.
Ahhh, totally understand, and me too.

Problem is, you don't have direct access to the batteries with these modules like you do with traditional lipo RC packs. These are "black-box", with a sophisticated BMS built-in, and between you and the actual cells.

You can't even check cell voltages directly, or balance them.

You can't overcharge or undercharge if you want to!

So, trust the Smart BMS, just charge and fly. Topping off won't hurt once in awhile if you find it's self-discharged under 95%, but I wouldn't make it a habit. Probably doesn't happen enough to matter as a share of overall cycles.
 
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Several years ago I purchased a Mavic 2 zoom battery discharger unit which I now can not find. Can anyone help me find someone/company that can supply a new unit? I believe there could be one that can be used for the Mavic 2 Zoom and a Phantom 4. Thanks.
Heeeyyyy! Sorry for such a really inexcusably late reply! You got the Phantom Angel... from me :) Still make this for whoever's interested... Can have a look at Phantom Angel
 
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