Rhino 5s1p 4900mAh 20C Lipo Problem - Page 2 - RC-Monster Forums

06.24.2009, 09:06 PM

ugg to late lol

Mentat · 06.24.2009, 09:10 PM

yeah im pretty new to Lipo, i got scared for a min. thanks for the tips. Im back on track

suicideneil · 06.24.2009, 09:13 PM

I've got one- its a really nifty little item, but I havent used the cell voltage recorder function yet, may have to do a little bench test just to see how well it works (cell voltage should still dip down a fait bit just blipping the throttle with the wheels attached). They also have an awesome wireless 2.4ghz version that lets you know the voltages whilst you are driving- now thats an epic feature, like a fuel monitor whislt you are driving so you know when to pit stop...

http://www.hobbycity.com/hobbycity/s...attery__869Mhz

Swanghobby also sell similar items, some abit funkier with LiFe compatibility:

http://www.swanghobby.com/battery-ac...ugs-c-209.html

Finnster · 06.24.2009, 10:31 PM

I've done this myself to speed up lipo charging if the V is too low, but how on Earth are you getting 18V when charging in 4S mode? 4.2V*4= 16.8V

Usually my charger will take it upto 16.8V in CV mode, so the amps slow down, and its not worth charging @ .2A.

I would not ever charge in NIMH mode. Yes you can cheat the charger to force a high amp charge into the lipos, but the charger will not stop running, and will raise the voltage to keep a high amp rate going. It never sees a V drop (like Nimh batts do when full) so it keeps steaming along even if the lipos go way over the 4.2V/cell limit.
This is a recipe to burn your house down. Do not do it.

FYI.. I did this once with an A123 pack before I got a usb adapter to update the charger for a LiFe mode. I got distracted for a sec, walked away, came back to late and my now 5S A123 pack was at 25V/5A and still going (should have stopped at 18V.) Destroyed the whole pack, but fort the A123s are inherently safe and did not burn. Lipos would have caused a fire.

You should just be able to select a 5S batt in the charger and go from there. In certain V ranges it could be a 5S or 4S batt, and chargers default to the lower count for safety. Just confirm its a 5S and go.

At the very worse if you can't, if your charger has a A123/LiFe mode, you may be able to use that mode as a halfway step for a little faster kick. Ie, for a 5S lipo pack, charge as 5S A123 to 18V (full charge is 3.65V/cell), then change to lipo mode.

Otherwise, don't let your batts go so low V. 3.2V/cell is a sfer cutoff, else, as soon as you fell the power start to drop, stop the truck immediately and change the batt. The last few mah kills the voltage and can ruin the batt.

Finnster · 06.24.2009, 10:32 PM

BTW, that thunder charger looks exactly like a Bantam b6 charger. Its prolly a relabel. Maybe that manual for the bantam will be more helpful.

Mentat · 06.24.2009, 10:52 PM

too late my house is burned to the ground and my 3 little kids are dead.... thanks SuicideNeil :(

06.25.2009, 02:05 AM

what battery tray are you using for that 5s? it says its 184mm long, is this true?

Mentat · 06.25.2009, 02:32 AM

Quote:

Originally Posted by big greg

what battery tray are you using for that 5s? it says its 184mm long, is this true?

i couldnt say now, thanks to neil my house is a puddle of melted electronics and little brittle bones from my kids. Just want you to know that they screamed his name while they burned.

Mentat · 02:36 AM

The 5s pack fits fine in my Losi Electric conversion battery tray, with room to spare.

update: pack is exactly 6.75 inches, oh and i replaced the kids off of www.ebaby.com you would be surprised at what you have to pay for a 4 year old these days.

junkman · 06.25.2009, 07:05 AM

Man, I'd go back and edit some of your post, they are your kids, so I guess you can joke about them how you please, but I think it is bs. Plenty of better ways to get your point across.

Finnster · 06.25.2009, 07:31 AM

0_o

.

suicideneil · 06.25.2009, 02:29 PM

I think he was joking... ...at least I hope he was.

Anyways Finnster, 4s = 18v because you only charge the cells upto 3.6v each, then stop the charge & restart it with the charger set for a 5s pack to achieve the full 4.2v per cell. Its a safety feature in many chargers- you plug in a pack, and if the voltage isnt high enough for the pack vs what you've told the charger it should be, then it will assume you're thick and charge the pack as though it were 1 cell smaller. Kind of annoying, but it does save people from tryign to charge a 2s pack as a 3s etc and burning down their house....

lincpimp · 06.25.2009, 02:39 PM

Quote:

Originally Posted by Mentat

i couldnt say now, thanks to neil my house is a puddle of melted electronics and little brittle bones from my kids. Just want you to know that they screamed his name while they burned.

06.25.2009, 02:45 PM

His name isn't SUICIDEneil for nothing.....

jzemaxx · 06.25.2009, 04:09 PM

Quote:

Originally Posted by suicideneil

I've got one- its a really nifty little item, but I havent used the cell voltage recorder function yet, may have to do a little bench test just to see how well it works (cell voltage should still dip down a fait bit just blipping the throttle with the wheels attached). They also have an awesome wireless 2.4ghz version that lets you know the voltages whilst you are driving- now thats an epic feature, like a fuel monitor whislt you are driving so you know when to pit stop...

http://www.hobbycity.com/hobbycity/s...attery__869Mhz

Swanghobby also sell similar items, some abit funkier with LiFe compatibility:

http://www.swanghobby.com/battery-ac...ugs-c-209.html

How does that Hobbycity batt monitor work with two batteries??? Can you only monitor one at a time?