richard.bratton

iTrader: (4)

Does anyone know how many manufacturers there actually are for lipo cells? I would imagine there are only a few... I only ask, because I've seen a lot of lipo packs of late and many look exactly the same with different stickers. It appears that many hard packs from different vendors not only include the same cells, but they also have the same external hard case. Back in the day, before lipo and NiMH, there was only Sanyo and Panasonic who produced cells. Manufacturers bought, matched, labeled, repackaged and sold these. If there are only a few manufacturers out there making lipos, we need to figure out which cells are the best and most durable, and then figure out who is assembling the properly. I never bought a matched pack of Sub-C cells without knowing who made the cells so why are we doing this with lipo?

Danny/SMC

iTrader: (2)

I'm not sure of the exact number but I know of 9 big manufacturers that can make high C rate Lipos suitable for RC. There are probably 10 small manufacturers that are able to make them as well.

richard.bratton

iTrader: (4)

Danny,

Thanks for the reply; I'm a little surprised by that number. Which cells are you using and why? Do cells from the different manufacturers have different characteristics other than C rating? It would be very interesting to see a comparison of the popular cells and which RC manufacturers are using what cells.

Rick Hohwart

The greater number of manufacturers involved is the good/bad about LiPo. The good is that there are many choices, price competition, and technology moving forward at a great pace with new and better product all the time due to heavy competition. The bad is that a product can become obsolete (perceived) in a shorter time than with NiMH.

In the LiPo field you are going to have to determine the companies you trust and who you are comfortable dealing with. Unlike with NiMH, companies like AE/Reedy and SMC (and surely others) are much more involved in the development of the LiPo cells and work in close conjuntion with the vendor. With NiMH, more of the devlopment was in the voltage enhancement and matching processes rather than in cell production.

Your best bet is to stick with a bigger company who can answer your questions, deal with customer service issues, and provide a quality product.

richard.bratton

iTrader: (4)

Rick, that's great advice. Thus far I've used packs from Orion, Losi, Trak-Power, and Trinity (Intellect) and have had great luck. All packs have performed great and proved to be pretty durable. In the case of batteries, I think you get what you pay for and all the companies above and have proved to provide great products for decades. The small premium you pay is worth it considering you know you are getting a seemingly good product.

What role do the RC manufacturers play in the production of the actual cells? I understand most of the cells are made in Korea. Do the cell manufacturers actually build cells for the RC industry to a tailored spec? I know NiCd and NiMH cells have mostly been the same batteries available in power tools and commercial/household applications and just adopted for RC. I suspect lipo cells are the same.

Rick Hohwart

More of the cells are made in China rather than Korea.

In the early days of NiMH, we were using cells that were power tool leftovers. This pretty much was the case for all cells made in Japan by Sanyo and Panasonic. Even in the big time of electric RC (25,000+ ROAR members), this was the case as R/C was small time compared to what was sold to Black and Decker etc.

Then the Chinese manufacturers become involved. These companies could work in smaller quantities and still be profitable which meant they could devlope product more quickly and make improvements on a regular basis. Even though R/C continued to use the power tool sub-c cell spec, the cells themselves were designed specifically for R/C cars.

With LiPo it is similar. These companies are profitable at lower volume and will make cells specifically for R/C use. the U.S comapnies are not actually producting the cells, but are providing the technical requirements and specifications so that the manufacturer can create cells with the expected performance.

Cain

iTrader: (294)

Danny/SMC: has there been any talk at any of the mags of having a "lipo shootout". Basically have the manufacturers agree to a testing methodology, and provide 3 - 5 of there best packs as a the same mah , and maybe a test of a companies "best" pack they have? I know the shootouts for cars happen ever so often, would love to see one for lipos.

Jube

iTrader: (43)

There was a pretty popular thread going on but has died off a bit on this question.
http://www.rctech.net/forum/electric...shoot-out.html

Danny/SMC

iTrader: (2)

We use an exclusive manufacturer that will only make high C rate Lipos for us. We have a very good partnership with them and we don't feel we need to give out there name as they aren't one of the big manufacturers and have no website. We have shown allot of info about our packs such as C rate tests and cycle life test that show our packs are high quality packs.

As far as cells from various manufacturers go there are differences in how they are built and the materials used to build them.

Danny/SMC

iTrader: (2)

I don't think such a test would be possible as doing a detailed test like our manufacturer does takes expensive testing/cycling equipment.

We have allot of good things planned as we want to show all testing info of each cell/pack on our website. I have already shared some info on this site to show how it looks and what our cells do under those tests. Looking to do a special section on our website to show how the tests are done and on what type of equipment.

Attached is the tester that is used to test for C rate. As you can see it's pretty big and costs 15 000 dollars to have custom built.

crazyjr

thanks Danny, I'll keep watch

rcflgator

iTrader: (4)

Why is it that only companies like orion, polyquest, flightpower, and i think thunderpower release info on their cells but others like maxamps....etc...etc don't say who manufactures their cells. interesting!

Jack Rimer

Why is that "interesting"? If the cells are well-represented in that the C rate is accurate and the performance/quality is as-advertised, why would it matter who makes it? Furthermore, if someone does have an exclusive with a specific manufacturer, why on earth would they divulge that source? I really struggle with this unnecessary need to know sourcing. If you go out to eat at a restaurant and have a great surf and turf, do you demand to know where the cow was raised or the lobster was caught? No, you just enjoy the meal and move on.

richard.bratton

iTrader: (4)

Jack, I see your point but I don't think the eating out comparison is relevant. I know when I shop for performance parts for my full size car, I won't by anything from an unknown manufacturer. Names like Brembo, Carbotech, Nismo, etc carry a lot of weight. Racing, full size or RC, is all about maximizing performance and I want to get what I pay for. Unknown commodities are generally a bad idea and most of the time when I've tried to save some money on no name parts, I ended up buying the quality product the second time around and paying more in the end. In RC, knowing the manufacturer of the cells may not be as important, but it's not unreasonable information for the consumer to have. If that's not going to happen, I'd at least like as much technical information as possible including tolerances, life cycles, and C rating. In the end, sticking with a well known and trusted brand that's been around for a while is probably the best option for all of us.

reenmachine

iTrader: (26)

Yes, and when you buy Brembo calipers you're not asking who they may or may not subcontract out the pistons to -- you're trusting Brembo to have assembled a top-quality product based on their reputation and your past experience with them.