Hi all, What is the preferred type of battery used? I see comments on SLA (which I used), LiPo and LIFE and am unsure which to use. The biggest ship I'll likely battle will be DKM Scharnhorst, I plan to build Mogami and the I-400. I do know that there are some restrictions with Canada Post as well as some cross boarder issues if I buy from the states. Where would a fellow from Nova Scotia get batteries from? The store used to buy them from is gone. Thanks, J
So I have decided on LiFePo and wonder if these are big enough to run the above mentioned ships, I get I would need more than on for Scharnhorst. How about Mogami? 1 or 2, all in parallel. Turnigy nano-tech 3000mAh 2S1P 20~40C LiFePo4 Receiver Pack
For a large ship like a WW2 Scharnhorst, you would want a lot more battery than those packs. Either that, or a lot of those packs. Also a 2S LiFe battery is still only 6.6v, you should look closer to 12v if you're planning on standardizing your boats and battery collection. Lots of guys still run 6v boats, but with modern tech its not necessary to limit yourself to that low voltage. For the individual LiFe cells a lot of guys here in the states use https://www.batteryspace.com/lifepo4rechargeablesinglecells1c-30crate.aspx and buy individual cells to build their own setups. Not sure on shipping into your area. (See post below for better Canadian source) I standardized my battery collection on 8AH (8000mah) 11.1V LiPo packs due to a great sale Hobbyking had last year, I bought up a dozen+ of them to use across all of my boats. One 8ah 11.1v pack is perfect for a heavy cruiser like a Mogami (for me, Suffren) two packs works great in a class 4 smaller battleship/battlecruiser (Courbet or Dunkerque for me) and then I chain together 4 for the real big power hog boats, like my Jean Bart and it's dual pumps.
Since you're in Canada, I would not recommend ordering lithium batteries from the US. Suppliers like Batterspace.com ship via UPS and they will charge obscene brokerage fees to ship lithium batteries to you across the border. I ordered my lithium cells from here http://www.evassemble.com/index.php?main_page=index&cPath=2 The blue headway cells are used by quite a few people and work well. Plus they are relatively cheap.
Thanks Will. Iooked at this site and ruled it out for just what Chase said, getting them across the border is very pricy, there is also another fee tacked on by the courier companies just for going across the border so I would have to add in the area of $85 extra, so they are out. Interesting what you said about 12V, I and everyone here always ran 6V but I will look into it, try to weigh the pros and cons. J
Thanks Chase, yeah I found that out. Do you think it is necessary to get the High C rated cells or will the standard cell be ok? I read yesterday (somewhere) about a balancing circuit that seemed to be required when battery packs are assembled, any ideas? Are there instructions anywhere wrt assembling battery packs, I have never done it before and I also read the LiFePo cells don't like being wet. Hell, a 2 cell pack will run the I-400 forever, as long as I can get the weight down. J
You don't necessarily need a high C rated pack, really depends on what kind of ship you are building. I see up above you posted a Turnigy RX pack, which might be ok for something like an I-400, which needs a smaller battery then the LiFePo4 batteries I posted a link to anyways, but not so much for something like the large Scharnhorst which would probably necessitate having a high output pump motor. That being said, I like the Headway blue cells mainly because of the energy density, and secondarily because of the C rating. You can charge the Headway cells individually, in which case no balance circuit would be needed. You might want to build in a balance circuit if you don't want to charge them individually, I haven't personally done this, so somebody else will have to chime in on what to use. I can't imagine its very difficult. To assemble the Headway cells into a pack, you just screw on a hoop connector connected to a wire with a hoop connector on the other end, then screw it into the appropriate pole of the next cell (ie. for series wire Pos+ to Neg- together, then the other end Pos+ and Neg- gets connected to your ESC for example). Lithium batteries don't like water, or air for that matter, which is why they are sealed up in a plastic pouch. So long as they are not damaged, punctured, left out in the hot sun (etc) you are fine. LiFePo4 batteries are more stable, so there is much less concerns safety wise, versus LiPO batteries (which are still usable, just need extra care & protection). I've been using lithium in various ships for over 6 years and the only issue I've had was one LiPO pack got puffed up because I left it out on the table in the hot Georgia sun.
Yeah good for cruisers and up, for the smaller ships you're probably still better off with the smaller Lipo packs from hobby King.
Looking at Hobby King, I seem to have the option of shipping from US or China, and from China there is no mention of any huge border fees from Fedex I think it was. Chase have you ordered from Hobby King and were there fees?
Looking at the charger I was thinking about, it does balance charges but there is another lead required. What charger do you use with the blue Headway cells? And can I get it from the same site?
I almost always order from the Hong Kong warehouse, partly because of the lithium issue, but also because they carry a lot more stuff then the US warehouse. The only fees you might get are GST, and even that isn't guaranteed unless the declared value is over $200 (HobbyKing will allow you to fudge that). The only reason you get hit with massive brokerage fees when ordering lithium batteries from the US, are because of their postal regulations. If I remember correctly, lithium batteries that aren't installed in a device, are required to be shipped by a carrier with a dangerous goods certificate when shipping internationally from the US. This of course, increases the cost of shipping even more, on top of which, UPS already charges the highest brokerage fees for international shipping into Canada. You don't have to worry about the brokerage fees if you can have stuff (just not lithium batteries) shipped out of the US via USPS. I use a Hitec RDX1 (bought from the local hobby store) charger on all my batteries, though you can use any charger that supports LiFePo4 batteries. Balance charging does require a third plug from the charger which connects to the balance lead on the battery pack. It is not necessary to balance cells charged individually (1s1p).
KK, so this one, https://www.horizonhobby.com/prophet-sport-mini-50w-multichemistry-charger-dync2030 that I can get locally would work. Good
It won't charge individual cells, but if you build packs with a balancing capability, it'll work. If you have a local hobby store, they can probably order you anything you see on Horizon's website. I'd personally go with something with a few more features but I don't know what kind of budget you're on.
Sooooo, next question. How does one build a LiFePO battery pack. I have seen the balancing circuits online and i suspect they are required. Would this be better in a new thread? I think so, Thanks guys, J
I just charge my cells individually (at the end of the day) and chain them together with a harness in the ship. Works pretty good. I have done quick charges between battles to the whole pack via the harness. Just to top them off.
