I plan to purchase the BR Lithium Ion battery 14.8V18Ah pack. However, to minimize the risk of the battery water tight enclosure not properly sealed every time the battery is taken out for charging and deployment, I plan to use waterproof connectors on the battery enclosure. What are the potential risks if I am charging the battery inside the watertight enclosure through the waterproof connector? Is it advisable to do so?
Hi Thesim,
Welcome back. A couple of issues that arise from charging within the housing is:
1, How will you connect the balance lead to the charger?
2, What connector are you planning or using? Is it rated accordingly?
3, In the event of a LiPo fire during charging, do you have a plan?
These are just a few concerns that spring to mind. I would look at other options to avoid charging within the housing; such as top side power supply or a second battery (both these option depends on the flights the ROV is needed for)
If you conduct a vacuum test before each flight (recommended) then there should be no problems with the water tight enclosure during a flight; also, the O rings should be replaced often if the battery flange is removed excessively.
The way the BlueROV has been designed, is to allow easy access to the battery for charging purposes.
My opinion would be to remove the battery and charge in a LiPo battery bag every time though.
Kind regards
Deep Supplies
Hi Deep Supplies,
1, How will you connect the balance lead to the charger?
-use another 6 pins connector on the enclosure for balance plug connection to the charger.
2, What connector are you planning or using? Is it rated accordingly?
-Planning to use BlueROV Battery Cable with Cobalt Connectors with 40A rating from Blue Trail Engineering.
3, In the event of a LiPo fire during charging, do you have a plan?
-if fire is a high potential risk I guess I will drop this idea.
This is for easier charging without opening the enclosure.
Hi Thesim,
I do not want to scare you with LiPo fire. I just wanted you to look at all problems that could potentially occur.
I recommend following the manufacturers advice when charging batteries and that is to remove the battery. Doing this, does allow a thorough inspection before charging. With out inspecting, it could potentially be wet.
Kind regards
Deep Supplies
Hi Thesim,
Thats the way that I am doing it and had zero problems. When in field i just connect a self made ±connector and charge it up. I keep the pressure test vent open during charging and once a week i balance the packs, both lipos and ions.
I was in the drone business for 15 years and never had a pack burning if you read simple warning signs (puffing, melted wires etc) also in the early days when there was no easy to get balancing chargers. Here is a pic of my setup, hope it helps.
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Hi josef,
Thanks for your sharing! It made me more confident to use this for charging.
Hey Josef,
I would also like to do this. I am using the BR charger with the additional balancing connector. How do you handle them?
Also, any info on the connectors you are using?
Thanks,
Bill W
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Any updates on this post? Did you end up using the cobalt connectors from BlueTrail @Thesim ?
@tony-white could you share your thoughts on this? I don´t expect you to advice users to deviate from the guidelines, but is this a possible path?
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Hi @Erlingns95 -
Using multiple batteries to power the ROV is fine - this is exactly what the BlueBoat does! The important thing is that each battery must be balance charged and connected when within 0.2V of each other. The batteries should be wired in parallel. Here is an example setup image recently shared with a customer:
The idea is good, but not really fitting our audience. Our target is to make something with as little “maintenance steps” as possible. Solely to reduce the chance of an “average Joe” making an expensive mistake.
Would you recommend NOT charging in a BR 4" aluminum enclosure? Even if the current was lowered and the “OK vent” was opened during charging?
Hi @Erlingns95 -
Charging in an enclosure should be fine, as long as it is a balance charge and not just topping off the overall voltage! Lowering the charge current and keeping the vent plug open is a good idea, in case something did go wrong.