2s Battery Question

CONNXT248

RC Noobie
Back with another question about the gremlin batteries;
When charging, do I need to have both the jst and the balancing port plugged in? I'm looking for a jst parallel charging board so we can charging multiple at once, but not finding any. This parallel board was recommended to me, but i noticed there was no jst ports, and I just want to be sure they can be charged without jst ports before our drone club purchases them.
 

Bricks

Master member
What you will need to do is solder up adapters from the parllal board to JST connectors, as my boards are XT60 connectors for the rest of my batteries so I solder the JST to them. You do not need to use the balance connectors every time you charge but I would get a board that has the balance connectors built in for future use.
 

sprzout

Knower of useless information
Mentor
Back with another question about the gremlin batteries;
When charging, do I need to have both the jst and the balancing port plugged in? I'm looking for a jst parallel charging board so we can charging multiple at once, but not finding any. This parallel board was recommended to me, but i noticed there was no jst ports, and I just want to be sure they can be charged without jst ports before our drone club purchases them.

Well, you can charge batteries without having a balance connector; sometimes people will do it for a fast charge. That said, it won't be a balanced charge.
 

ElectriSean

Eternal Student
Mentor
I'd recommend changing over to XT30 connectors, those JST-RCY connectors are only rated to like 9 amps. I've not seen any parallel charge boards with them either. Here is an XT30 parallel board. There are some cheap chargers that only use the balance plug to charge, but they are very slow and wouldn't work in a parallel configuration. Most chargers charge through the main leads and use the balance plug to discharge for balance. And BTW, you should always be balance charging, there is really no good reason not to.
 

CONNXT248

RC Noobie
I'd recommend changing over to XT30 connectors, those JST-RCY connectors are only rated to like 9 amps.
Problem is that we (my school's drone club) already bought 16 gremlin batteries with JST so its a bit late to change over.
What you will need to do is solder up adapters from the parllal board to JST connectors.
So just solder a male xt30 straight to a male JST and everything will charge fine with the parallel board ElectriSean suggested?
 

ElectriSean

Eternal Student
Mentor
You will need a male JST-RCY and a female XT30. Remember that the gender of the connector is determined by the pin and sleeve, not the plastic connector body. You can also change the connectors on the batteries, just cut, solder and shrink tube one wire at a time to prevent shorting it out.
 

bitogre

Member
It really depends on your charger. Most charges can only do charging through the main charging leads (JST in your case). The balance port is for monitoring individual cell voltage and to discharge a individual cells to ensure each cell is not over charged by discharging the cell with the highest voltage down to the same level as the other cells. While you can sometimes get away with charging without connecting balance charger, you are more likely to have a problem (over charging can result in a fire).

Personally, I do not like parallel charging. Yes, many people do it safely without issue. But if you make a simple mistake, you can damage your battery and/or parallel charge board. You need to make sure that all batteries are at roughly the same voltage (within a 0.1V or 0.2V). If you do not, when you hook the batteries in parallel, the high charged battery will charge the lesser charged battery without anything to limit current. As such, you can put too much current through the wires (melting them which I have done) and possibly damaging the batteries itself.

I know it is a little more expensive but I use a multi-port charger that can charge multiple batteries at the same time independently. There are several advantages including it being safer and that the batteries do not have to be at same level of discharge. You can start the first battery charging as soon as you finish your first flight and add additional batteries after each flight on a new port.