How to charge P4 battery without charger

[Helihover]

Blown out if the water how?

The “car charger” steps up 12v to 17.4V, we might say that is boosting the voltage?

Cmon, You and I know exactly what that’s called. It’s called a power inverter. No one refers to a power inverter (especially one who claims to be a designer (another word for engineer?)) as a power booster.

The gent up above who claims to have designed Lipo chargers stated that chargers have a power booster....... lol

We’re not even talking about chargers anymore as these “items” are not chargers as stated by you. They are simply power supplies or if you have a car charger, it’s a power inverter.

You guys both have contradicting statements ATM.

Quit trying to twist words and you’ll get a bit further with me.

 

[Helihover]

Think about your 2 cell charging setup. Was it only the balance leads connected? I suspect you also had the main battery power leads going to the charger also. I charge up to 6 5Ah 6cell packs on occasion. All balance leads and main power connections from packs are parallel connected to the charger.

This is how multi charing power boards are wired...

The cells (in each pack) are series connected to the charger- FACT....

View attachment 92955

Two channel, not 2 cell.

I’m still waiting to hear from the designer of chargers for any further comments.

 

[With The Birds]

Two channel, not 2 cell.

I’m still waiting to hear from the designer of chargers for any further comments.

Thank you, I meant to say “2 pack” call it 2 battery for absolute clarity).

 

[With The Birds]

Cmon, You and I know exactly what that’s called. It’s called a power inverter. No one refers to a power inverter (especially one who claims to be a designer (another word for engineer?)) as a power booster.

The gent up above who claims to have designed Lipo chargers stated that chargers have a power booster....... lol

We’re not even talking about chargers anymore as these “items” are not chargers as stated by you. They are simply power supplies or if you have a car charger, it’s a power inverter.

You guys both have contradicting statements ATM.

Quit trying to twist words and you’ll get a bit further with me.

Your wrong again..... electrical engineers will, and do frequently in common parlance, refer to the subject circuit as a boost converter.

Twisting words? Hmmm- that’s an interesting take.

You launch here with great confidence telling people they are wrong and then continue to dance around arguing a subject you seemingly have limited knowledge in.

I strongly suspect @alokbhargava could design and prototype a boost converter circuit for this application with little trouble- as can I an likely many others who frequent this board. It is basic engineering.

 

[Helihover]

Your wrong again..... electrical engineers will, and do frequently in common parlance, refer to the subject circuit as a boost converter.

Twisting words? Hmmm- that’s an interesting take.

You launch here with great confidence telling people they are wrong and then continue to dance around arguing a subject you seemingly have limited knowledge in.

I strongly suspect @alokbhargava could design and prototype a boost converter circuit for this application with little trouble- as can I an likely many others who frequent this board. It is basic engineering.

Awesome.

I only said you and the other designer were wrong.

I was strictly talking about Lipo chargers and not power supplies or power inverters (you might not understand those words so) AKA Power Boosters. I stated this earlier and took your statement as true, meaning I believe what you say.

Twisting words is not interesting actually. When you call a power inverter or power supply a “power booster” to gain the upper hand, that’s twisting words. Be a man and call them what they are like everyone else does instead of trying to sound like someone your not.

Peace and happy flying!

 

[alokbhargava]

Awesome.

I only said you and the other designer were wrong.

I was strictly talking about Lipo chargers and not power supplies or power inverters (you might not understand those words so) AKA Power Boosters. I stated this earlier and took your statement as true, meaning I believe what you say.

Twisting words is not interesting actually. When you call a power inverter or power supply a “power booster” to gain the upper hand, that’s twisting words. Be a man and call them what they are like everyone else does instead of trying to sound like someone your not.

Peace and happy flying!

Who said Power Booster? Do you know what a power booster is?

Do you understand a difference between a voltage booster and power booster?

There are LiPo chargers and LiPo chargers with balancers

There are LiPo batteries and smart LiPo batteries.

 

[With The Birds]

Awesome.

I only said you and the other designer were wrong.

I was strictly talking about Lipo chargers and not power supplies or power inverters (you might not understand those words so) AKA Power Boosters. I stated this earlier and took your statement as true, meaning I believe what you say.

Twisting words is not interesting actually. When you call a power inverter or power supply a “power booster” to gain the upper hand, that’s twisting words. Be a man and call them what they are like everyone else does instead of trying to sound like someone your not.

Peace and happy flying!

Actually, fact is that @alokbhargava and I, with respect to comments posted in this thread, weren’t wrong.

You post #5 you stated the OP needs a LiPO charger. What he needs is a regulated 17.4V power supply with a connector to suit the battery.

Then at post #6 you say that “chargers don’t have boosters” and disagreed with Alokbhargava‘s claim that chargers working from a 12V supply to charge a higher voltage battery have a boosting mechanism. Again you were wrong. Your suggestion that chargers “charge by cell” and that you need no more than 4.2V to charge any liPO was also incorrect.

Alokbhargava then explained that a battery cant be charged “by Cell” if the balance taps aren’t available and then detailed how a typical “boost converter” operates. He was correct on both counts.

I also informed you that the cells in DJI batteries are charged by series connection (the charger sees full battery voltage). Seemingly in an effort to maintain your earlier incorrect assertion you claimed I was wrong and must be as auto Lipo Chargers (you qualified this as specifically true for DJI Chargers) “charge off each cell” and that if they “charged in series they couldn’t balance”. Both your claims here were wrong.

You seemed to have accepted my explanation as to how the DJI charge circuit is implemented and of course you are correct in your observation that the DJI “chargers” are in fact nothing more than a DC power supply. Whether “boost converter”, “inverter”, “switch mode” or other other name might be most appropriate to describe the circuit topology is of little relavence.

I am unsure how you might have formed the view that Alokbhargava and I made conflicting statements. It can be easily demonstrated that what we had presented in response to your claims is correct.

As to “being a man” there was no word twisting. I cant speak for Alokbhargava however I suspect his intent was no different to my own. That is an interest in healthy discussion to ensure what is presented here is factually correct. I am more than happy to be corrected, it usually results in learning something and happens frequently. From what I am seeing it might be you who might respond badly to correction.

 

[BigAl07]

Come on gang.. we can argue and disagree without making it personal (on either side).

 

[Stevie_UK]

I'm pleased I don't do drugs!

 

[N017RW]

It seems there are a great deal of
semantic issues in this discussion.

But to those who argue that each cell
in a series constructed LiPo pack is charged independently... how does that work given the + terminal of one cell is connected to the - of it’s neighboring cell?
How do you manage the polarity difference each individual cell requires at their junction?

This is why typical (non-DJI) LiPo packs have a charge/discharge connector across the end cells and a balancing connector at the cell junctions.
Yes they can be combined into a one connector form-factor but the terminations are explicit.

 

[With The Birds]

It seems there are a great deal of
semantic issues in this discussion.

But to those who argue that each cell
in a series constructed LiPo pack is charged independently... how does that work given the + terminal of one cell is connected to the - of it’s neighboring cell?
How do you manage the polarity difference each individual cell requires at their junction?

This is why typical (non-DJI) LiPo packs have a charge/discharge connector across the end cells and a balancing connector at the cell junctions.
Yes they can be combined into a one connector form-factor but the terminations are explicit.

Absolutely- and that is precisely how the DJI cells are wired.

 

[wa5tef]

Chargers can’t charge by cells if end points of each cell are not exposed.

One of the ways to boost DC voltage in these DC to DC converts is to use L-C circuit with high frequency chopping. Inductive energy is pushed to capacitor and voltage rises. There is a control circuit to maintain required voltage and limit the current.

I know this cause I was a designer.

Hmmm, sounds reasonable to me!
Jim

 

[wa5tef]

So, it seems that the original operator never got his charger?
Thanks,
Jim
WA5TEF

 

[Marcio Valerio]

Right.......

The charge circuit is in the battery, have you wondered why it needs 17.4VDC on the input to charge a 4cell series LiPO pack? Simple because the cells are charged in series. There is no mystery as to how cell balance is achieved. Bleed resistors on the cell taps (R1-R4) are switched in on the highest voltage cells.

View attachment 92950

I am sorry to disabuse you of your notion however fact is the car charger adapter also supplies 17.4V to the pack, it uses a simple switch mode inverted to increase the voltage.

This circuit is for P4 intelligent battery, correct?
I need a similar schematic diagram for P3 intelligent battery...

 

[jerry1957]

No they don’t. Chargers don’t have “boosters”. Where did you arrive at this?

Chargers charge by the cell. You need no more voltage than 4.2 to charge virtually any LiPo. The charger type will determine how big of a battery you can charge. All the amps and “power” voltage etc. come from the power supply (car battery, dedicated power supply, wall transformer), the charger disperses this voltage accordingly.

There are many 12v charges that use a buck-boost circuit to charge batteries of higher voltage than the source. I have adapted my HP laptop charger that uses 12v from a cigarette lighter and outputs 19.7v to charge my drone from a motorcycle.