Smoking NIMH batteries

[Titan1]

Hi I hope somebody can help me.

I had a stock Supervee 27 and decided to upgrade the hull. I purchased a Titan 29 hull and installed the Supervee's running gear with the exception of the motor. I upgraded that to an AMMO 2300kv. I also installed an Octura x440 metal prop. The problem now is that I kill the batteries after just 3 or 4 runs. The batteries come out at about 200 degrees. The speed controller and the motor are cool as a cucumber. I have no clue why the batteries would be so hot but yet the electronics are cool. On new batteries the boat runs really fast until they fry. Help what am I missing?

Here is a run down of my setup

Hull Titan 29
Motor Ammo 2300KV
ESC stock 45 amp Supervee ESC
Prop Octura X440
Batteries - Duratrax 6 -cell DTX 3800 NiMH

[Doby]

The batteries can't deliver the current the motor wants to use, thats why they are hot. NiMh batteries time has come and gone. get LiPos and problem solved.

[Jeff Wohlt]

Too much amp draw on the cells. Go with lipo and you will be faster and cooler. Minimum of 25-30c and at least 4000 mah.

With that setup you are lucky you have not burned the boat down. Round cells are good for about 40 amps and you need 80+ for that set up.

Actually I am surprised that motor is not cooked. Big hull and high KV= poof!

[sjslhill]

question

Those NIMH packs are welded are they not? A soldered pack of 4600 NIMH would work well, but they are correct, most are using LiPoly now

thanks,
Steve

Hi I hope somebody can help me.

I had a stock Supervee 27 and decided to upgrade the hull. I purchased a Titan 29 hull and installed the Supervee's running gear with the exception of the motor. I upgraded that to an AMMO 2300kv. I also installed an Octura x440 metal prop. The problem now is that I kill the batteries after just 3 or 4 runs. The batteries come out at about 200 degrees. The speed controller and the motor are cool as a cucumber. I have no clue why the batteries would be so hot but yet the electronics are cool. On new batteries the boat runs really fast until they fry. Help what am I missing?

Here is a run down of my setup

Hull Titan 29
Motor Ammo 2300KV
ESC stock 45 amp Supervee ESC
Prop Octura X440
Batteries - Duratrax 6 -cell DTX 3800 NiMH

[Titan1]

I don't know if they are welded.

[sjslhill]

Where did you purchase them? Are they a === stick?

[Titan1]

These are the batteries. I http://www.duratrax.com/caraccys/dtxc2145.htmlhave been running

[JMSCARD]

These are the batteries. I http://www.duratrax.com/caraccys/dtxc2145.htmlhave been running

Yup the are welded... That's your problem too... A side by side cell layout with deans ultra bars and deans solder would be fine with those cells... The junky "welded" tabs are terrible as they cause terrible resistance.... What are you running for connectors from the actual battery pack? Tell me not the Tamiya plug they came with?

[Titan1]

No I would never run Tamiyas. Everything I run is on Deans.

Can you give me a recommendation on a good pack?

[Flying Scotsman]

5000 mah 40C..it may be wise to change out the esc as well....bullet connectors also

Douggie

[JMSCARD]

No I would never run Tamiyas. Everything I run is on Deans.

Can you give me a recommendation on a good pack?

http://www.hobbycity.com/hobbyking/store/uh_viewItem.asp?idProduct=10282&Product_Name=Turnigy_4500mAh_2S_30C_Lipo_Pack

if you are just buying for this boat..... I myself try and buy the same batts so I can use them in series and parrallell in a bunch of boats..... if you were to go that route I would get the turnigys in a 5000mah 40c variety that way if you get higher amp draw boats in the future you can still use your other lipos.... if you want to stick with nimh's I would look for some like these... I used to run smc matched packs in my boats before the lipos became reasonable price and were not as "scary" anymore..lol...

http://cgi.ebay.com/4200mah-Intellect-Matched-6-cell-Race-Battery-Pack-35A-/180548560283?pt=UK_ToysGames_RadioControlled_JN

If you look around or go to a local "rc car/truck track... many folks may give you good deals on used "matched" batteries as they are going to lipos often now too... GP3300 cells were also used for years in high amp draw boat applications.... they are good cells that are durable too..... the 4200 intellects like to be cycled and don't take well to not discharging all the way down.... man just talking about these nimh packs brings me back to my pan/touring car days.... we used to have a couple "turbo matchers" and I still have two turbo 35 gfx's that I don't wanna sell because I paid so much for them and now they go cheap.... Id rather keep them for the "legacy" of it all...lol...

[sjslhill]

If you want to stay NIMH, we can build you some very good packs.

thanks,
Steve

[Alexgar]

these

http://www.hobbycity.com/hobbyking/store/uh_viewItem.asp?idProduct=10098

[Alexgar]

or these

http://www.hobbycity.com/hobbyking/store/uh_viewItem.asp?idProduct=11598

[sjslhill]

I would use these

http://www.hobbycity.com/hobbyking/store/uh_viewItem.asp?idProduct=11934&Product_Name=Turnigy_nano-tech_5000mah_2S_25~50C_Lipo_Pack