Back into R/C - Advice on NiMH
 

Been out for years now. Batteries have really changed Seems LiPo is the way to go, but storage of LiPo is more than what I want to worry about. Any brand of NiMH that is good and where to get them?

thanks.

No. What you're looking for in NiMh doesn't exist.

You have LiPo in your house already. Your cellphone, laptop, tablet, all have LiPo's in them. If you're worried, throw your car's battery into a lipo safe, and store it on, something non-flamable.

Let's say I only run my car 1 a month, will LiPo still be the better way to go?

If you're running as a basher what battery you run doesn't matter. If you want to be able to compare your car to anything on a track these days, you absolutely need lipo. LiPo batteries are just fine being stored for months at a time. Mine frequently go months between use.

For sure, you just have a few new things to learn and remember - need to use a lipo specific charger, and store at storage voltage (most chargers have a storage charge mode - 3.8-3.85V per cell).

Some people are super pedantic but you don't need to be, as long as they aren't stored fully charged or fully discharged for long periods they're fine - i.e. anywhere in the middle is pretty safe.
Once you follow the simple rules they last much longer and work better than NiMH in general. No memory effects, flatter discharge curves, lighter, lots of other benefits.

You can also take a look at LiFePo4 batteries. A bit lower in voltage but due the lower resistance more equal with NiMh in performance.

I too semi-recently got back into R/C cars. Not being too familiar with the in's and out's of R/C lipo care, it was a little concerning at first the 'extra' handling needed. However, it's not really that big of a deal. Just a few things to do:

1. Make sure your ESC has a Lipo Cut-off feature. Most of the modern ones will, but some of the older ones do not.
2. When you aren't going to use the battery within the next week, do a storage charge on it.

It's really that simple. If you want to make it more simple, just do a storage charge after you have run the vehicle (and after the battery has cooled a bit).

I've been looking at brands now. I bought myself a Hitec X-2 black edition charger. I also have a mp9e on its way and dug up an old rc-10 for my son. what brand and lipo are suggested for the mp9e and rc-10? not going to be racing it competitively, and don't want to overspend on my first lipo. saw that trinity and reedy have a good selection. is this brand decent as when they were back in the days?

If you aren't competing, then just get whatever fits your budget. ;)

Personally I have used a lot of promatch batteries as:

- Great performance for the price
- Fast Priority mail shipping, and usually free too
- Great warranty

The should be able to cover your battery needs easily

I'd add store your lipos someplace that remains cool. Garages, sheds, the truck of your car in the summer are terrible places to store them.

The Hitec X2 will be a great, versatile charger for you.

As for batteries, there are 3 types of Lipo batteries cells, and everyone uses one of them. High end cells that end up in $70-100 2S packs that squeeze more performance out of the battery. These are a great choice if you're professional or semi-professional racer or someone that wants to think a better battery will improve their bad driving. You're paying for good quality cells and also some extra attention paid to testing and matching the cells in the pack.

Midrange cells which end up in many of the brands that have been discussed in this forum. You should be able to pick these up for $30-50 for a 2s standard sized battery. I've had multiple batteries purchased at different times from the same company where most are great but some are terrible. But since these usually cost half what the high end ones do, even if 1 out of 5 is a lemon, I'm saving money that can be spent on something else (better motor, servo, tires, etc)

And then finally there are the cheapies. These are the ones you'll find on Ebay and Amazon, from companies no one has heard of. They might be OK, if you're just playing around in the yard or if you have a really light vehicle. With these, you're getting what you paid for.

If you're running an 1/8 buggy, don't even bother with the cheap batteries, these heavy and high power vehicles will destroy them.

Nick Adams over on Youtube, does a lot of testing of batteries, motors, etc. He recently did a mega test of 1s batteries. His test showed that most of the batteries after a fixed amount of discharge (4000mah) where within .05v of each other. Which can probably be attributed to slightly different capacities or manufacturing tolerances.

Figure out what your budget is. You'll find that most batteries of a particular cell count, capacity and C rating are pretty much in the same price point across lots of companies. Find your best deal with shipping and go driving.

Funny thing about this, was one of the first in the region running converted 1/8 scale nitro vehicles back when we were using Neu motors combined with MaxAmps (yes, those guys when prices relative to performance were actually good) "HIGH Capacity" 6000mah 4S 20C (Yes 20C) lipos were something great from what I recall. This was at the start when people tried liked 3000KV motors on 4S was common. We modified castle creations mamba ESCs by bypassing the BEC and opening up holes in the case with a fan to keep it cool. It actually worked great. Ran a high cutoff on the lipos, and you had a good performing reliable 1/8 vehicle, and the lipos lasted well too due to higher cutoff. and this is when we wree pushing 20 minute mains.

Biggest sign back then when a lipo couldn't handle the load , or at least one of them, voltages per cell could be all over the place, raising cutoff helped this.

So, these days, we are kind of spoiled. 10 minute mains should be easily doable for a 4500mah or greater lipo with a 1900Kv or so motor and not running tons of practice laps, even with a smaller C battery size like 40 - 50C, etc.

3 or 4 cell pack for the mp9e
2 cell pack for the rc-10