Thunder Tiger Crawler - lipo battery

[pitadavespa]

Hi,

My name is Luis and I'm from Portugal.

First of all, I'm a complete newbie in this area, so...

I was offered a Thunder Tiger Crawler last Christmas and I'm looking for some mods/upgrades.
I ordered 4 metal shocks and a rear steering "kit", but I'd also like to replace the battery, not only to achieve more playing time but, mainly, to improve performance.

My questions are:

1 - Is lipo the right way?
2 - It's being hard to find a lipo battery with a good quality/capacity that fits inside the battery box. I have no problem moving it outside but, since I want to keep the gravity center as low as possible, what do you recommend?

Thank you very much and regards,
Luis

[pitadavespa]

I tested the crawler with an additional battery, in parallel, and I didn't notice any change regarding performance. I guess this means that one is enough to the crawler's needs.
I think, if two Nimh don't give any extra boost, a Lipo won't do it also. Am I right?

I'm thinking in keeping the extra battery, though, because it extends running time and because the additional weight (I placed it, literally, under the hood, aligned with the front servo) helps to get more front traction when climbing.

Do you guys have any recommendation?

Thanks ;)

[crawlhog]

lipos are much better and lighter than the NIMH batts you are running. and come in different sizes.
without knowing what electronics you are running its hard to suggest a battery.
2S ?
3S ?
what are the specs of your ESC?

[lemonhead]

lipo is the way to go , plus most of the time there also cheaper than NIMH.
but you do need a lipo charger and balancer, just something to think about.
once i switched it was like night and day.

[Charlie-III]

Originally Posted by pitadavespa

I tested the crawler with an additional battery, in parallel, and I didn't notice any change regarding performance. I guess this means that one is enough to the crawler's needs.
I think, if two NiMH don't give any extra boost, a LiPO won't do it also. Am I right?

I'm thinking in keeping the extra battery, though, because it extends running time and because the additional weight (I placed it, literally, under the hood, aligned with the front servo) helps to get more front traction when climbing.

Do you guys have any recommendation?

Thanks ;)

Running the 2 batteries in parallel means you ADD the capacity (which usually means runtime).
If you ran them in series, you would add the voltages.
This is why you didn't see a performance change other than "time on course".
How many cells are in your current battery packs??

To see if you can "up the performance" all of us need to know the ESC spec's, then we can determine if more voltage will give a boost in performance.

And yes, if you go to a LiPO battery, you need a proper charger & ESC (or an add-on to the ESC for low voltage shutoff).

[pitadavespa]

Thank you all for your help.

The batteries I'm using are 7.4v 500mAh (Nimh). If I go LiPo, it will be 2s.

Yes, I know the differences between running batteries in parallel and in series. The idea of adding another battery in parallel was that I was "hoping" that one battery, alone, didn't had enough current to the motor and servo. So, adding another one in parallel would boost performance, since it doubles the available current.
Since I didn't notice any difference in performance, I'd say one battery is enough for this motor/servo needs.

The ESC is a Veloci Geko, 20A . I guess 20A is the max current it handles?

The motor is a 280. I believe it is similar to this one: http://www.jameco.com/Jameco/Products/ProdDS/232005.pdf
If I'm seeing it right, the max current needs will be 2.9A.

So, I'm not sure if a LiPo will make any noticeable difference regarding performance. What do you think?

Thanks.

edit: I don't have a proper Lipo charger.