P3S Charging or Not?

[solentlife]

Bill ...... you appear to be confusing CC with CV .....

CC is usually a format used with a User programmed charger where you can charge different battery's etc. Unless the CC is low enough to be safe to be a fixed rate for a specific use.

If your 12A 5V supply you connected was CC - then it would try to thump 12A into that USB connection. It would not care about what its connected to.
As you say it will only supply 1A because that is what controller demands - that shows your supply is CV.

Nigel

 

[solentlife]

Page 18 of the manual referring to battery LED's also talks % ..... not cycles.

Cheers
Nigel

 

[BillW50]

Bill ...... you appear to be confusing CC with CV .....

CC is usually a format used with a User programmed charger where you can charge different battery's etc. Unless the CC is low enough to be safe to be a fixed rate for a specific use.

If your 12A 5V supply you connected was CC - then it would try to thump 12A into that USB connection. It would not care about what its connected to.
As you say it will only supply 1A because that is what controller demands - that shows your supply is CV.

Here I'll try to elaborate. For example, I have on my work bench a variable CC/CV power supply. I can dial any current (up to 5A) and any voltage (up to 32V) I want. So let's say I dial up 2A @ 4.2V. CC means constant current and CV means constant voltage.

Now if I connect this up to a discharged LiPo 3.7v cell, the current will likely slam 2A into it, but the voltage will probably fall to say 3.6v or so. As the LiPo charges, the power supply will put out higher and higher voltage (this is CC mode) till it reaches 4.2v. It will continue to charge, but the voltage won't increase anymore. Just the current will start to decrease (this is now CV mode). Once the current drops to 100ma, it is considered fully charged. Leaving it connected is considered overcharging. And this is how LiPo chargers work. The better ones slowly ramp up the current in the beginning instead of slamming it with high current from the start. Which is said to be hard on LiPo's.

Now connecting the controller to 12A @ 5V isn't going to thump 12A into it. That can't happen unless 5V increases. The most the controller will ever draw is 1A @ 5V. And it will continue to do so until it is somewhere about 90% charged. Then the current will start dropping.

 

[BillW50]

Page 18 of the manual referring to battery LED's also talks % ..... not cycles.

Cheers
Nigel

Page 18 states the percentage (9 different patterns to crudely represent somewhere between 0-100%,) is based on the number of cycles. Here's their wording of the same meaning.

Checking the Battery Life (page 18)
The battery life indicates the number of cycles can be charged and discharged before it must be replaced... When the battery life reaches 0%, the Intelligent Flight Battery must be replaced.

 

[solentlife]

Here I'll try to elaborate. For example, I have on my work bench a variable CC/CV power supply. I can dial any current (up to 5A) and any voltage (up to 32V) I want. So let's say I dial up 2A @ 4.2V. CC means constant current and CV means constant voltage.

Now if I connect this up to a discharged LiPo 3.7v cell, the current will likely slam 2A into it, but the voltage will probably fall to say 3.6v or so. As the LiPo charges, the power supply will put out higher and higher voltage (this is CC mode) till it reaches 4.2v. It will continue to charge, but the voltage won't increase anymore. Just the current will start to decrease (this is now CV mode). Once the current drops to 100ma, it is considered fully charged. Leaving it connected is considered overcharging. And this is how LiPo chargers work. The better ones slowly ramp up the current in the beginning instead of slamming it with high current from the start. Which is said to be hard on LiPo's.

Now connecting the controller to 12A @ 5V isn't going to thump 12A into it. That can't happen unless 5V increases. The most the controller will ever draw is 1A @ 5V. And it will continue to do so until it is somewhere about 90% charged. Then the current will start dropping.

Bill - you now add in the info - your supply is user variable .... your previous was just 12A / 5V .... no mention of variable.

Second - your explanation about CC and voltage etc. agrees with my comment also about LiPo charging. Initial stages are CC, then final is CV. But what you left out there is that you as the user set the current and cell number.

You then suddenly jump back to 12A / 5V .... Bill if you connected a CC supply set at 12A to that controller with its rated output at 5v ..... goodbye controller !

USB charging is CV .... not CC anyway ...

Nigel

 

[solentlife]

That page 18 is like many other parts of the manual 'ambiguous' as it does not state clearly number of cycles - this 200 figure seems to be a magical figure that despite a lot of searching I cannot find given by DJI themselves. Maybe it was - but if it is true that 200 is a setting - then DJI should be prepared for very very bad press given that average LiPo is good for considerably better life than that !

Question is - has anyone actually had a battery refuse to charge / work at that figure ? If someone can come forward and state absolutely they have more than 200 on their battery or its died - that would help a lot.

Nigel

 

[BillW50]

Bill - you now add in the info - your supply is user variable .... your previous was just 12A / 5V .... no mention of variable.

Second - your explanation about CC and voltage etc. agrees with my comment also about LiPo charging. Initial stages are CC, then final is CV. But what you left out there is that you as the user set the current and cell number.

You then suddenly jump back to 12A / 5V .... Bill if you connected a CC supply set at 12A to that controller with its rated output at 5v ..... goodbye controller !

USB charging is CV .... not CC anyway ...

Nigel

Well the variable supply was used to elaborate what CC and CV is all about. And yes, I do sometimes use it as a LiPo/Pb charger too (not often). But I didn't use it for the controller's USB port. There I did use an USB 12A supply (my variable power supply only puts out 5A max, remember) and there is no adjustments on the USB 12A supply except for the power on/off switch.

 

[solentlife]

Hi Bill ..... have we moved to another playing field ?

A USB 12A supply ..... I'm amazed - the official technical standards for a USB connection are nowhere near that high rated .... you are looking at 60W through two thin contacts only rated to a fraction of that .....

What is that designed for ? And to be honest that further cements my comment its CV with only potential to supply 12A if demanded.

Nigel

 

[BillW50]

That page 18 is like many other parts of the manual 'ambiguous' as it does not state clearly number of cycles - this 200 figure seems to be a magical figure that despite a lot of searching I cannot find given by DJI themselves. Maybe it was - but if it is true that 200 is a setting - then DJI should be prepared for very very bad press given that average LiPo is good for considerably better life than that !

Question is - has anyone actually had a battery refuse to charge / work at that figure ? If someone can come forward and state absolutely they have more than 200 on their battery or its died - that would help a lot.

That is what I am saying about the magic 200 number. Litchi reports the battery life as a value between 0 and 100%. DJI battery only states it in like 12% steps. Litchi's value is like 10 times more accurate. And 11 recharges and 98% battery life means 1/50th of the battery life is gone. That means I should have 50 times more battery recharges than I have. That would mean like 500 recharges before the battery life reaches 0%. But we will know more in time and if others share their battery life vs. number of recharges values we will know more sooner.

 

[solentlife]

Bill - if I could I'd buy the beer !

So we wait for DJI to answer my email and / or someone on forums to say what their battery did ....

I have to admit that eventually I want to find a way to replace LiPo in the DJI case at a fraction of their pricing.

All you have to do is check out pricing of a 4S HV 4500 LiPo .... and you'll see my point.

***** just rec'd email from DJI saying they are reviewing my request.

Nigel

 

[BillW50]

Hi Bill ..... have we moved to another playing field ?

A USB 12A supply ..... I'm amazed - the official technical standards for a USB connection are nowhere near that high rated .... you are looking at 60W through two thin contacts only rated to a fraction of that .....

What is that designed for ? And to be honest that further cements my comment its CV with only potential to supply 12A if demanded.

Nigel

Yes it is indeed rated as a 60 watt power supply. Am I likely to pull 12A through a single USB? Naw, not likely. But it's a good supply to test those 2A-4A fast USB charging claims. If this supply can't, nothing else will either.

 

[BillW50]

Bill - if I could I'd buy the beer !

So we wait for DJI to answer my email and / or someone on forums to say what their battery did ....

I have to admit that eventually I want to find a way to replace LiPo in the DJI case at a fraction of their pricing.

All you have to do is check out pricing of a 4S HV 4500 LiPo .... and you'll see my point.

***** just rec'd email from DJI saying they are reviewing my request.

Nigel

Yes same here Nigel... cheers.

Ah ok... I got ya. I thought about trying it too. It would be very easy to clip my power supply up on those two battery tabs in the battery bay and see if the Phantom accepts it as power without freaking out. The only thing I heard so far is only the DJI GO App checks for a DJI battery. It seems the Phantom and the controller could careless. And if you need an App, the Litchi App could careless what battery you are using either.

 

[solentlife]

At $500 for my P3 - I'm a little wary of connecting a pack without DJI's 'intelligence' in place.

I'm wondering if a pack can be opened and lipo itself changed. People such as Banggood sell the outer plastic case - makes me wonder why ......

Nigel

 

[BillW50]

I thought of an easy way to test the P3S getting power without the rest. Those two extra battery connections is I bet is a serial communication port of sorts. Just taping over it and plugging the battery in will have the same effect.

Wow I didn't know that Banggood sells just the battery shell. Very interesting. While I was there I noticed that they also sell a clone battery that works even with the latest firmware they claim. Virtually all of the comments are really positive about them. A couple also mentioned that they work the same except these don't self discharge. That is one thing I don't like about DJI batteries. As I can discharge my own batteries, thank you very much!

 

[solentlife]

As I understand it - there are two sets if connections that have specific jobs.

The main power connection where we charge and power the flight motors.
Second smaller are the telemetry power connection and for battery data.

The Banggood shell has no board or connectors as I understand it. So it may be a shell to replace any that get broken in a crash or mishap.

I will be sitting with my pal when I get home and pooling our electronics knowledge to see about this replacing lipo matter. If as DJI reply to me said that 200 cycles is just a warranty number - then that may mean there is no limit to life - which may mean it won't care if LiPo is replaced as long as power is maintained while swapping over. I can see myself saving a bundle on battery's !

If I succeed - I will create a webpage detailing it all as I believe in community - not hoarding !

Nigel