18650 li ion battery usage in model boats
|phill downes||10/07/2021 19:54:37|
14 forum posts
Been looking around the web and I see 99% of model electric boats are now running the expensive Li-Po batteries.
What I would like to know is why are the 18650 Li-Ion batteries not being used ?
The 18650 type are far cheaper than Li-po cells and from what I gather could last a fair amount longer as in duration on a model boat..
I think I can lay my hands on a fair amount of Li -ion batteries from a dead electric scooter and wondering if these would be just as good to use in my boat. I am not sure how many cells are in the scooter as yet as ive not taken it apart to find out ( waiting for it to arrive) but been assured the cells are perfectly good. I think it could be 36 volt pack ?
The voltage I am after is just around 12 to a max of 24 volts. and these 18650 would be so much lighter than a pack of Li-Po for the same amount of volts. I am not looking for a super screaming boats,, just some batteries to use on a MFA Barracuda motor in a 37 inch planning hull pilot type boat. if I run 24 volts this would be at a maximum draw of 6 amps ......or at 12 volts 4 amp loaded....
any information on using / or not using the 1865 batteries would be well received
|ashley needham||11/07/2021 07:32:40|
7323 forum posts
Phil.i think you will find that most boats run on Nimh batteries. Just because you see the use of Lipo cells in fast boats doesn’t mean that everyone uses them.
A fair few people still use sealed lead acid types for tugs etc as they need the weight.
Nimhs last physically much longer thanLipo, and if you don’t need the weight reduction are not necessarily the first choice.
Is an MFA barracuda motor ok with 24v?.
Sorry know nothing on the other type of battery. Not heard of it being used for models.
|Richard Simpson||11/07/2021 09:01:03|
649 forum posts
From my own experience at my club I would very roughly estimate that Li-Po batteries are around 10-20% of the usage.
Of the remaining, most small boats use either NiCads or NiMHs and large boats tend to use gel type lead acid batteries. I think a lot of modellers occasionally fall into the trap of thinking that brushless motors and Li-Po packs are the be-all-and-end-all of performance when they have overlooked the fact that they do not need the performance. In most cases, unless you are into very high speed models, reliability should be a more important consideration.
Let's face it we still race Club 500s with a brushed motor and NiMH batteries so there is enough performance in that set up to provide entertaining racing.
Finally you mention cost, in this case there is no contest as a NiMH will give you plenty of performance and duration for a fraction of the cost of comparable Li-Pos or Li-Ion.
I am actually very wary of any Lithium based battery as there can still be a tendency for them to be unstable both in use and during charging, what other battery uses a "blast bag" for charging? I would be very reluctant to start playing around with some that are used and were not designed for the purpose for which you are considering.
Edited By Richard Simpson on 11/07/2021 09:01:33
|Ray Wood 2||11/07/2021 09:15:45|
2485 forum posts
My only observation is that Li-Ion are used to power laptops and I don't believe they are as volatile to the charging methods as compared to Lipos which main advantage is they are light in weight compared with NiMH and great for aeroplanes.
I'm sure you will get a much more technical reply from somebody who knows more about electrics.
Fast discharge Lipo's is required for fast models so the "C" rating has to be around 30 in my experience not based on any theory just practice.
|Malcolm Frary||11/07/2021 09:53:32|
|1029 forum posts|
One of my members, as part of his business, winds up with lots of laptop battery packs that have ceased to be workers. He strips them down, checks the cells (which are invariably 18650s) and uses the good ones to build packs to power his boats. Cruisers rather than screamers, but having roughly the same power demands placed on them as they had in their native laptops, they work very well. And, of course, to him they are free.
To drive his hooligan boats he does pay real money for proper batteries.
|Colin Bishop||11/07/2021 10:00:20|
4967 forum posts
Richard, I would be surprised if NiCad batteries are much used these days as the EU banned sales years ago except for certain specialist and replacement purposes. The original packs must be on their last legs by now due to memory effect.
|Richard Simpson||11/07/2021 12:09:55|
649 forum posts
Thanks Colin, I didn't even know they were banned!
|phill downes||11/07/2021 14:37:45|
14 forum posts
these motors were known to run upto a x70 type propeller.
the motors were often fitted in the mfa Fairey Fantome but at 12 volts were rubbish in those boats. They needed 24 volt to even just get on the plane, and back then people were running 2x12 volt SLA so weight was realy high.
Motors are very much like the old smiths windscreen wiper motors and old heater motors from cars ( even the late ford cars ) run a motor almost the same for the heaters.....
Edited By phill downes on 11/07/2021 14:51:49
|phill downes||11/07/2021 15:04:32|
14 forum posts
By the way , you can still buy ni cads here in the uk.
here are just a few places found straight away that sell Ni cads.
nothing illegal about them.
the law as far as I can see was only to stop power tools coming with ni cads in them from new, but nothing to stop you replacing them .
|Malcolm Frary||11/07/2021 17:15:03|
|1029 forum posts|
In the model boat world, even if NiCad are available, since NiMH with better numbers at lower prices are so readily available, why go that way? For most of us, NiMH is a direct drop in replacement for NiCad, and, in packs, without the "memory" of myth and legend.
Please login to post a reply.
Want the latest issue of Model Boats? Use our magazine locator link to find your nearest stockist!
Make sure you never miss out on the latest news, product reviews and competitions with our free RSS feed
We welcome well written contributions from Website members on almost any aspect of Model Boating with a particular emphasis on practical hints, tips, experience and builds.
In order to maintain a consistent standard and format, all suggestions should first be sent to me by Personal Message for approval in principle. Only a very limited amount of time is available for editing contributions into a suitable format for placing on the website so it is important that the material is well presented, lucid and free from obvious spelling errors. I think it goes without saying that contributions should be illustrated by appropriate photos. I shall be happy to give advice on this.
The Member Contribution area offers space for short informative mini articles which would not normally find a place in Model Boats magazine. It is an opportunity for Website Members to freely share their expertise and experience but I am afraid that virtue is its own reward as there is no budget to offer more material recompense!
I look forward to receiving your suggestions.
Colin Bishop - Website Editor