Running ESC directly to Bullets - Charging
 

All my batteries have female bullets and I have been running an adapter (Male 4MM Bullets to Female Deans) and using Deans Male plug on the ESC. I was thinking of bypassing the Deans and going straight from the ESC to Male bullets. Are you guys that are running this setup just charging your batteries in the car using aligator clips or pulling the plugs each time. I use ProTek 4MM bullets which fit super snug so if I can charge without pulling them out that would be sweet. Will it damage the ESC to charge that way?

Charging your batteries while still in the car and plugged into the esc is a very BAD idea for a couple of reasons and I will explain why.

1st, If you've ever witnessed or watched a video of a lipo fire, you would know that things can go pear shaped quicker then you would expect. With charging in the car you're at risk at damaging or destroying your car if something goes wrong and can't remove the battery in time.

2nd, Leaving the battery plugged in while charging could have serious consequences especially if you forget to turn it off, you could damage not only your esc, but also your receiver, servo, motor fan and personal transponder if you have one.

To charge my batteries I have a adapter like yours which is bullets to a female Deans plug, then I have a male Deans on the charger. I do this because that way I don't have 2 bullet connectors laying about from the charger output that could possibly touch each other and short out the charger.

In my car I use bullets soldered directly onto the ends of the positive & negative input wires of the esc.
One tip to do though is to make either the positive or negative wire shorter so it can just reach one side of the batteries terminals, and therefor can't be plugged in the wrong way if you're rushing or not concentrating at the time.

It's best off to be safe and remove the battery from the car when you wish to charge it and place it in a fire retardant container. A few extra seconds of time gained isn't worth risking losing your car, equipment or worse getting badly injured, play it safe.

Cheers
Rob

Excellent points! Thank you for the very thorough post. I really like the idea about making one of the leads shorter.

If you look past all the reasons not to do it..

IIRC I want to say that I've seen a pic of Ryan C. charging with the esc plugged in using alligator clips.

Funny, I pulled up his base setup from PetitRC and there is a picture of him doing it. But alas I don't get free cars or batteries so I will err on the side of caution:lol:

I agree with most of your other points, but....


How?

How? when the ESC is on its pulling current from the battery. if you charge it while its on, your forcing current into it.

Its ok, you drive a Miata.

I agree on most points, but are there still chargers around that are not immune to reverse polarity and shorting?

Because when charging the voltage goes above 7.4 volts.

That is true, however there's still that risk of shorting out producing a significant spark and an electric shock, it's not a pleasant experience being zapped by a charger, sure it may not harm you but still a hazard. I know it shouldn't happen but for some reason I received a zap from it, I no longer have that charger btw.

Also, what if you drop one of your tools and it shorts the terminal of the battery while it's charging in the car, that could also lead to the battery shorting out, which again could have dire consequences.

Likewise, makes sense to minimise the risk of damaging your equipment rather than gaining a few moments of time.

Cheers
Rob.

Forcing current?:lol:



Your battery is also over 7.4v when you plug it in.


It wasn't that long ago that charging with the battery soldered into the car was common...

Until people started to burn them up by either not following the guidelines & instructions, or when the charger failed to stop charging either from incorrect settings or internal failure.

That's why you don't see anyone doing it anymore at racing events be it club, state, national or world events.
Especially at major titles events, having a team & sponsored drivers car go up in flames would not do well for publicity.

Cheers
Rob.

I also had a similar slight zapping experience once, and thought the charger is bad, I measured the leads with a multimeter, but every point was at zero, so I put it down to the surface of the connector must be old and slightly gritty and cause the feeling in a purely mechanical way. I soldered on another connector and had never had such feeling since.

I can imagine making an accidental short while charging in a car, so I don't do that whenever possible. Only exception is a small car that has a terrrible mounting system, so if I don't have to wrench it, I leave the pack in and cover it with a towel.