Large Scale Central

New to bat. op: 11.1V vs 14V? need to understand more, please

Electronics Power and Sound
#1

OK. I’m new to battery operation. And I don’t live close enough to my club members to run over and look at how they’ve done things. So I will be starting to mod my B’mann LS Heisler to battery and intend to, “try,” to get everything in the loco’s oil bunker.

The 11.1V LiIon batteries were recommended to me so far. I just spent time this AM searching back through this forum looking for battery info, (lots there - just sift through it), but I don’t see the 11.1V bats mentioned much. (I’ve been considering that in the 3-cell package) I will never have long trains or long running times. And I will always be using slow speeds. I will use Revo and Phoenix P8 sound. I did find tons of commentary about 14 volt batteries. So I remain confused about which voltage range I should buy. Help?

Future locos here that I hope will soon run on battery are the B’mann Climax, (old version), 3-T Shay, 2T Shay and Connie. I doubt my retirement funds will allow all that very soon, but…

It was also recommended to me, for space manipulation reasons, to consider a pair of 7.+V, 2-cell bats and series them. (Which, of course, is back up to the 14V range)

Evidently the three electrical components in the loco that consume power do not care if it arrives in the 11.1V or 14V version. I read that my Phoenix will accept up to 30V, so plenty of tolerance there. How about the B’mann motors and anything else? Any voltage sensitivities or limits to be concerned with?

Sorry for the long post. I need to order batteries, so I figured I’d ask. Thanks for reading all this, Dennis

#2

I use a mix of 11.6 and 14.4v, depending on which locomotive. Most RC systems need sometging above 10 (?), so it’s good there. Less voltage will give you lower top speed. But the speeds I run at, it doesnt really matter. Go for the most MAH that you can fit. MAH (milliamp/hours) = runtime.

#3

Voltage = speed, and amps = runtime. Volts X amps = Watts, which equals grunt power, or the ability to get the thing moving with a heavy load up a hill.

I know there are those who will say that I am out to lunch on this, but…

#4

Dennis you have to look at the manufacturers requirements for voltage when choosing batteries. You are using a Revo control system that requires a min of 12v to operate but will shut down the system over 24v. That is why all of us who have the revo control system use the 14v to 21v batteries. The Airwire control system requires less voltage so the 11v batteries are OK.
I’m sure the voltage requirements are different for every control system out there.

#5

If the Revo needs 12V and you want to use LiIon, then it looks like you will be forced to use 4 cells for 14.8V. You can use two 7.4V two cell packs in series if it helps you fit everything in. I did that in my Porter - two cells in each side tank.

I run RailBoss systems and they are quite happy with 11.1V. In all of my self contained conversions I’m using 14.4V. I run 11.1V sometimes in my trail car behind a Bachmann 45 Ton and it runs fine.

The best way to choose your battery voltage is to run the loco n track power and measure the voltage at the highest speed you want to run. Then add a few volts for overhead in the electronics.

#6

Thanks everyone. I did talk to MW today and got confirmation on a couple things, mostly what the good replies here told me later. I have a pair of 7.4V’s on order and will series them for the right voltage and use their individual pack size to allow better fit options.

And because of all you and quick replies, I also got in on the battery sale at All-Battery.com

Thanks again,

Dennis

#7

Sounds good Dennis. Once the packs are wired in series be sure to charge them as a 4 cell 14.4v pack, If charging individually (with them disconnected from each other) charge as a 2 cell 7.4V pack.

#8

I know I am late on this but another thing to remember when using battery with phoenix P8 is that the Phoenix needs 9volts to operate. An 11.1v LiIon battery has a cut off of 7.2 volts so part way through your operation you may lose sound. The 11.1 volt battery has a peak voltage of (I think) 13.2 volts. They don’t stay there long, then they hover around 11.1 for the majority of the charge then drop off. It’s one of the redeeming qualities over NiCad or NiMh which show a constant steady drain from time of charge to discharge while using.

A 14.8v LiIon battery has a peak voltage of 16.2 and a cut off of 12 volts. So, you get sound throughout the entire operation.

Just some more stuff to log away for future reference :slight_smile:

Terry

#9

Good info Terry. When I run an 11.1V pack in my trail car which has Phoenix Sound (I think it’s a P8) I notice that the volume of the sound will fall off a few minutes before the batteries shut down. I don’t loose it completely, but 60% or more reduction in volume.

#10

Terry Burr said:

SNIP
It’s one of the redeeming qualities over NiCad or NiMh which show a constant steady drain from time of charge to discharge while using.

Terry

Sorry Terry, not so.
Both NiCd and NiMh have a higher initial voltage when fully charged and drop to the nominal voltage quickly. They hold that voltage until almost discharged and then crash quickly.

Perhaps you are thinking of Lead Acid Gel cells that do discharge in a linear fashion.

#11

Good info here. I wonder if my thinking was off…

I also thought the Voltage of your battery packs would determine how much “stuff” you could run on your loco.

Such as: If you run a 11.1 V pack and your ESC and motor need 10V then you only have about 1.1 V left for running other accessories like lights, smoke units and anything else you might want.

I always thought if I could get higher voltage in my batteries then I had “room” to add accessories to my loco if I wanted.

Am I off in my thinking?

#12

A little bit Jake. Amperage is the factor that determines how much “work” you can do. In the case of battery packs, a pack with a higher MaHr (Mili Amp Hour) rating run more items, or run one item longer.

A good analogy that most can understand is water. Voltage is like Pressure. Amperage is like Volume.

#13

I use only 14.4V on most everything. Passenger USA diseasemals getv 16.8, the Dash 9’s, SD-45’s, Mikado and Mallet from the late Aristo need 16.8V.
To give you an idea:
Battery Backshop (Terry Shellenberger, LocoLinc) only used 12V lead acids. Not good. LGB Moguls so equipped would stall on grades with a train.
I have never had a stall on 14.4V.
Would I use 11? Maybe in a critter, but not for what I do.
You don’t need the extra, don’t use it, as in don’t go full throttle.

Use 11.1V and you may be sorry satisfaction-wise.

TOC

#14

I also use mostly 14.4/8 volts.
19.2 volts nominal for the big 6 axle dismals and some big brass steamers.

For Thomas and Friends I limit the voltage to 9.6. That gives a plenty fast top speed.

#15

I converted a Bachmann Indy to battery use with 11.3 (measured at the motor) volts because that’s about all the battery I could fit in the thing. It performs OK, not a high top speed but good enough, and it can pull 16 axles up my 3 1/3% grades. It’s not what I would have chosen (like others who have posted I normally use 14.4v), but it works OK

Steve