Home        Store        Docs        Blog

Charge the battery,as you can do with laptop?


(Roar) #1

Hello

I wonder,is it possible to send power down to the bluerov2 to continuously charge the battery (Lithium-ion Battery (14.8V, 18Ah)
as you can do with laptop?

I have look at Deep Trekker,they have a Hybrid-Power System,to send power to the ROV’s
internal batteries to continuously charge the unit while it is plugged in.

I use a seabotix cabel (8.9mm) it has 6 shielded wires,two of them is 17AWG,the rest is 24AWG.

Do QGroundControl or software need to be modify to continuously charge the battery?

Can you use a Battery protection board with Balance and connect power to it,to continuously charge the Lithium-ion Battery?

Have no clue how it works.


(Heinz) #2

it would be difficult to charge the battery without the balance board connector in place to monitor the charge of the cells


(Etienne Demers) #3

You can use a BMS (battery management system) such as this one: https://www.aliexpress.com/item/4S-14-8V-16-8V-20A-peak-li-ion-BMS-PCM-battery-protection-board-bms-pcm/32817069499.html?

What you have is a 4S6P (4 stack in series of 6 batteries in parallel) Its a similar BMS inside the surface charger.

If you do decide to go this way I would suggest two sets of batteries and a changeover circuit like the one posted in the other post. http://www.alpsdrone.it/products-services/uav-2/battery-cut-off-system/


(Roar) #4

Very good idea to have two sets of batteries and changeover circuit,but then you need to have exstra enclosure and the Payload Skid.(the BlueROV2 will be much higher and heavy,i like the height and weight as it is now)

What output voltage,should be to charged the battery?

Isolated DC/DC converter I’ve found has only 60W (4Amp) i can use three of them (12Amp)

These Isolated DC/DC converter is very expensive,but best quality.

Isolated DC/DC converter can not be bigger,it is very small place in the battery Enclosure,but it is enough space for 3-4 60W.

Can you trust on this BMS printed circuit board? was very cheap.

Does this have any impact on the QGroundControl or software to Bluerov2? (Voltage measurement,Amp measurement,Safety settings)


(Etienne Demers) #5

Have a look on digikey, mouser or RS. You will find there are several DCDC converters much more powerful.

IE the BMS, I would trust it. Everything is made from China nowadays and you would be surprised on production costs when they have large orders.

In the end there is really not that much on this board…


(utku atay) #6

@an-ron could you please share your results about issue? Have u tried that hybrid system?


(Roar) #7

Everything works,but the battery charges only with 2 amp.(measured with a ammeter)

I do not know why, (when i try the system,the battery was 15.3 volts when i connected the charger to battery,after 4-5 hours the battery was full 16.8 volt) bluerov2 was ON.

The DC/DC converter i use is Traco Power TEN 60-4813WIN i use two in parallel,will give out 6.5 amp/16.8 volt.
The BMS Board with balance have max working current 30 Amp.

Works just fine,except the amp.



(Rusty) #8

Hi Roar,

Cool! Is this through a tether? If so, how long?

-Rusty


(Roar) #9

Yes,through a tether 170 Meter

Tether is a seabotix cabel (8.9mm) it has 6 shielded wires,two of them is 17AWG,the rest is 24AWG.

I send 75 volts down to bluerov2.


(utku atay) #10

@an-ron you said bluerov2 was on so what was the power consumption of rov when you were charging? As i know bluerov2 works over 40A when %75-%100 gain mode on, your BMS board can not handle with it. Have u checked any other BMS which fits the tube?


(Roar) #11

you said bluerov2 was on so what was the power consumption of rov when you were charging?

I had only bluerov2 on,sow it was only 0.90 amp without the light and Thruster.

If you use the bluerov2 at 25 -%100 gain mode always or light on without a break,the battery will not charging, because the battery is only charging at 1.8 Amp.

The BMS board can handle 30Amp you don’t need any bigger,because the battery 18Ah can only be charging at 10-15 Amp :grinning:

Have not figured out why the battery only charging at 1.8 Amp,should have charging at 6-7Amp need to measure a little more.


(Rusty) #12

Hi Roar,

Does the BMS handle 30A charge or 30A discharge? A BMS that could handle 30A charge would be pretty substantial. That’s a lot of current. Handling 30A discharge and a few amps charge is more likely I think.

Do you have a datasheet or something for the BMS?

-Rusty


(Roar) #13

Hello
The BMS can handle 30A charge and 30A discharge according to info.


(Roar) #14

I have now remove the BMS from bluerov2,i have measured again and battery is only charge at 1.8 Amp that is not sow much.

Did not find out why battery only charging at 1.8 Amp,should have charging at 6-7Amp sow maybe it’s BMS board.