NiMH batteries in WTC - H2 gas problems?

[bradv]

Hi,

I'm in the initial stage of converting a Trumpeter Kilo to R/C and the crux of my design depends upon battery placement. I'm planning on using 6 x NiMH cells and for simplicity placing them in the WTC. However, on investigating battery chemistry, I see that hydrogen is only produced as part of the normal recharge cycle as follows] + OH1-

For charging, I plan to leave the batteries inside but ventilate them well. For discharging, the primary current draw will be a 6v Graupner 140 (through an ESC of course). The batteries are 3.5Ah, so I don't think I'm going to be overloading them.

The theory is that there's no H2 produced when discharging, however being a little paranoid about the sealed environment of a WTC, I'm wondering how concerned I should be about not separating the batteries from the rest of the components (including motor, servos, switches etc.) which may possibly spark?

I know that, for example SLA batteries also vent H2 (they're not totally sealed!) and should not be put in a WTC. I haven't heard any horror stories (yet) about NiMH's in the WTC, and I don't want to be the first. I don't have the room to make a separate battery compartment like in my Akula as the Kilo is rather small. I could try & seal them off from the rest of the WTC, but this would be a real pain so my preference is to have everything in the one WTC.

So, in the vast experience of the SC members, is having NiMH's inside the WTC a good idea or not?? Thanks for any info/experiences!

[anonymous]

Bradv,

I also converted a Kilo.

Bradv,

I also converted a Kilo.


Trumpeter Kilo Conversion

I'm using 600 AR's. 6 total. They also vent. 1100 nimh's are the same size. 6 fits easy in the forward compartment. I think you'll find there's a lot of room in that small sub.

Take a look at my thread and also be sure to look at what Big Dave did as it was the starter for my WTC.

I see no problem with using nimh's or nicads.

Hope this helps some,

Steve

[bradv]

Thanks U812,

For simplicity and also

Thanks U812,

For simplicity and also due to materials availability, I'm only using one compartment. So whereas I know that NiMH's are fine to run the sub, it's whether putting the batteries in the same compartment as the electronics is a good idea or not?

[anonymous]

Brad,

Here's a pick of the

Brad,

Here's a pick of the Kilo WTC with nicads. This compartment is separate from the others. I think it's best this way. I've noticed that most of the sub builds have the battery either outside wet or in it's own compartment.

Hope this helps,

Steve