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[RogerG]

Hi All,


need some advice on installing brushless motors.  My question is, do you HAVE to use Li Po batteries or will a NiMH or a Sealed Lead-Acid be suitable. Many thanks in advance.
Regards,
Roger G

[tsenecal]

you are not required to use any specific battery type.  the ESC may be tuned to offer options based on the type of battery...  ie built in low voltage cutoff.   some may be tuned for lipo voltages, with no option to choose a different type.  something to look for when selecting the ESC.

[DaveM]

Volts are volts - the motor won't know or care where they're coming from. That said, NiMH packs should be OK but I would strongly advise against using a SLA battery. The power required would very quickly flatten one of those old dinosaurs. If you have one then either retire it or save it for a tug (or hand it in at the nearest police station). They weren't intended for the level of current-drain required by even a modest motor. They also make good weights or doorstops...

Do take Tsenecal's advice about setting the low-voltage cutout on the ESC. NiMH packs are 1.1v/cell whereas LiPo should be >3.4v/cell.
DaveM

[malcolmfrary]

If the brushless motors are doing the same job that brushed motors were doing, the same power supply will have the same reasults.  SLA are good for combining ballast with a modest current supply.
The most common application for brushless motors so far has been fast boats, where weight saving and high power are both needed.  In that type of boat, having got the required motor power and saved a bit of weight using a brushless motor, there is little point in weighing the boat down with a big lump of lead.  Fast boats tend to use a lot of power to go fast - this means high current continuously, almost certainly more than an SLA would be capable of delivering for more than a few seconds without causing itself damage.

[chas]

I use brushless motors in 2 of my models with NiMH batteries without any issues. The 2 models are both fast scale, not racing boats so don't need very high power, only sufficient to do the job properly.. One of them is a Thornycroft, 1 meter long, lightweight build. I use a 2826 10 1400kv on 9.6 volts. Flat out it looks far too fast to be a convincing scale model, so I run on about 3/4 throttle, with occasional fun dashes up the lake. I can sail for 35 to 45 minutes.
 Lead acid batteries? I have 2, they're in a ferry model, it needs a lot of ballast.
I hope that helps a bit.


Charles

[john44]

Hi Roger, looks like you are just starting up with this hobby. Have you got any batteries?
More important have you got a battery charger. If you haven't a charger go for a multi charge
unit that does most battery types we use now, Nimh, lipo,s etc.
Nimh are probably the way to go, not lead acid.
You don,t say what type or size of boat it is you're thinking of putting the motors in.
As already stated if it is a fast boat lipo,s are better but require safety measures when charging
Also low voltage warning units fixing to their balance leads when in use.


John

[graze]

Just out of intrest is there a reason your against using LIPOS?

[DHutch]

Just out of intrest is there a reason your against using LIPOS?

Its a good question.


I am new to the hobby, having raced RC cars in the in the early 00's  (NiMH, but just before brushless became mainstream) and for me the fear of LiPo is probably mainly just the unknown nature of them.


Risk of fire is often cited, and is also a consideration, but mainly just not really knowing where to start. As well as having existing chargers for NiMH/NiCad.


I know for cordless power tools they are now mainstream, and also recommended for infrequent use as the self discharge is low.
Looking briefly at what is for sale, it appears that cost wise LiPo appears to be on par with NiMH these days.
At which point while it is a given for power to weight, maybe LiPo is the way to go for most applications now?


LiFe batteries also appear to be making an entrance, and appear they might be a reasonable option for boats?