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Tattu 1800mah 4S 75C Review and Testing
Tattu 1800mah 4S 75C Review and Testing
I was recently sent one of the new Tattu 1800mah 75C 4S batteries to do a bit of testing. I've been flying it for a week or so and I have spent some time gathering data. Here is what I've found so far. To give a bit of background, I am a multirotor pilot, and am primarily interested in miniquads.That being said the testing I've done applies universally. These high C rated batteries are useful beyond the bounds of multirotors into the world of 3D flying, and high performance aircraft. For this test I've done some stress testing (and unintentional abuse!) and general data collection with this battery, and for comparison purposes a Dinogy 1800mah 65C as well. I did a current draw test on both batteries at 25A to measure voltage drop. For now I have skipped the internal resistance test as my current tester seems to be giving unreliable results. I will post an update as soon as I get some reliable results. Finally I recorded a flight with an onboard current and voltage sensor in the OSD to demonstrate voltage drop in real world flight conditions. Physical Characteristics As with the GensAce 2200mah I reviewed last week, my first impressions of this battery are very positive. GensAce/Tattu seem to use the same build techniques in both their lower discharge and higher discharge batteries. It has the same aluminum support that covers the battery and adds additional protection to the top and bottom of the battery. After a bit more research I have found that this actually provides compression during high discharge and according to research can significantly extend the life of the battery. Again, where the high current lines enter the battery casing they are re-enforced with additional heat shrink. The balance leads also come out the opposite side of the casing rather than the same side as the high current lines. In addition this battery has a plastic cover that extends over the balance lead cables, preventing stress on the cables when plugging and unplugging the balance cable. I will point out that on some chargers this can prevent the balance leads from fitting properly. Unlike the 2200mah, this battery came with XT60 connectors, which means no soldering for me. Battery dimensions actually exactly the same as the 2200mah 3S, and are accurate to the product description on the sellers website. The wight is just over 200g and the physical size is 105mm x 35mm x 25mm. Because of the aluminum plates the size is very consistent.    Load Testing I wired the battery up to a 25A load to test voltage drop. At the top of the battery the voltage dropped mostly linearly at a rate of 0.037V per A. That leads to a projected drop of 1.9V at a 50A load.  The flight video shows a voltage drop of about 1.5V at 65A which is actually a good deal higher than the projected ratings. Granted this sag was at the top of the battery, and this was the batteries first flight, however it leads me to believe that the performance of these batteries increases as the amp draw increases. It appears to be a factor of the carbon nano-polymer used to increase the C rating. Also it is worth noting that on this first flight test, I got a bit caught up in flying and pushed it a bit harder than I was planning. The battery came down screaming hot and a tad unbalanced at 0.10V maxium variance between cells. However after a few hours of cool down the battery was back to withing a 0.03V maximum variance. After a slow charge the battery was perfectly balanced. After several additional flights there seem to be no ill results from the abuse on the initial discharge. I am very impressed with the handling of the abuse!
Comparison Load Test For comparison the Dinogy battery performed slightly worse with a 0.043V per A drop.  Conclusions My initial impressions of these batteries both in build quality and performance are very positive. Because of the very high C rating, it is hard to get an accurate picture of whether or not this battery can fullfill a 75C (135A) current load, but given very few people have a setup that can draw that type of constant load, that's not something we can easily gauge. Since I haven't found a reliable method for testing internal resistance (other than the load tests above) It's hard to get an objective measurement of true C rating. I will post an update as soon as I can test these on a more reliable tester. I can say up to 65A loads this battery performs excellently. I was also very impressed with how well it recovered from first time abuse. The battery provides both solid performance and the extras in the build such as the reinforced cables and aluminum compression plates add up to a very nice battery. However that battery does come at a premium price compared to other similarly rated batteries. For those interested, the battery is available here: http://www.genstattu.com/tattu-1800m...tery-pack.html UPDATE 08-05-2015 Here is a video update on my thoughts after a month or so of flying these. Also worth noting I am borrowing a Hyperion charger that tests battery IR during the entire charge and discharge cycle, and the numbers I am getting on it are within a couple percentage points of the numbers posted on my initial review, so that is encouraging. Again, worth noting that IR is only one part of the picture, and isn't always reliable as a measure of actual performance. These have kept performing on par with my 65C Dinogy 1800mah though (unfortunately those are near end of life now, so their performance is starting to drop off compared to this one), so that is encouraging.
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Last edited by QuadMcFly; Aug 05, 2015 at 09:11 PM.
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The dinogy has about 12-15 cycles, and is only about a month old, at the point of the 25A load testing testing the Tattu has about 6 cycles in it. Due to the fact that batteries have a break in period, the Dinogy may actually have a slight advantage here. That being said the difference in voltage sag between the two was not that significant, and seems inline with a 75C compared with a 65C. I didn't include it here, but the voltage sag in flight was similar as well, On my crappy IR meter the Dinogy tests a bit higher than the Tattu, but that probably doesn't mean much. I'm getting a good quality IR tester from a friend today. After a dozen cycles or so he tested his Dinogy at 55C, after an initial test of only 32C. When I get the tester i'll compare IR's.
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Lipos have the highest voltage under load when there brand new. After some cycles have been run they equalize a little and the high voltage peak comes down a little. Your testing looks good. You just need to get a high res Wayne Giles meter to get more accurate results.
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Eh, it's just typical Chinese "salesmanship". Some of their stuff is pretty overpriced, but you can get pretty good deals on it if you watch out for sales. The quality is top notch, so it's worth watching for price drops. For instance the 2200mah 3S 25C tested out at over 35C and is available for $8.99. Also the 1800mah 45C is only like $30 full price. I agree that some of their marketing tactics are a bit off though. And obvious to boot! Just like any of the Chinese companies though, you've got to know what to look for.
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Excellent and very detailed test and review. I also got one of these for testing and also found it to be as good as my Dinogy 1800-65C-4S. Price is a little higher about $8 more but so is its C-rating. As you described the battery pack is very well made, I would say is the best cell packaging I've seen and used.
Seems this particular size as well as the 1300mAh packs are in very high demand thanks to all the minicopter hi-power setups of choice nowadays: 2204-2300kv/2206-2000kv/2208-2000kv mated to 5045BN & 6045 props just to name a few. I'm running RTFQ 2208-1800kv motors/6045 props in my miniquad. All those setups really torture batteries. They're very Amp-hungry. You definitely need this high-C rating LiPos to be able to do frequent full throttle stints, lesser batteries just can't deal with the high current draw, so there's a price to be paid when running hi-power setups. I didn't do as detailed test as you (impressive) The extent of my testing was just flying and getting the feel of how its charge was delivered. I noticed no voltage sag. My flying skills are not top-ace but I do manage to get the low-voltage alarm beeping on my lesser C-rated batteries after the inevitable full throttle punch out (otherwise where's the fun of having a hi-power mini?). I would say this would be a good choice of battery for any hi-power minicopter. Yes it's a little higher priced than other options but it is a very well made battery pack. Here's my video of the flight test I did
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Those are 65C, Tattu LiPos are 75C Pricing and availability are virtually identical http://www.genstattu.com/tattu-1300m...tery-pack.html http://dinogylipos.com/4-cell-65c/207-1300mah-4s-65c |
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This little mini review is nice. And seeing how these packs are built does make me want to try them even more. But imgumby is totally right about the tattu/gens ace shills. I mean they have even gotten into your review thread here with ridiculas comments. It's not so much this thread but they just kept trying to market here on the forum and breaking the rules over and over to the point where I refuse to let myself buy from them. And it's a shame because the build quality is great your right. And looking at your results looks great also. It's really irritating to me because i want to try one. The truth is had they not acted like they have I would already own many of there packs.
It would really tic me off if I started a mini review thread and they come in with there ridiculas comments like they did to you here. Even to the point where they talk back and forth to each other knowing darn well it's the same person. I just wanted to point this out to try and show them there marketing techniques are way to obvious and if anything loosing them Buisness here in the forum for sure. I'm in now way saying your part of this trust me I feel your review is what you have experienced and you did a great job with putting the build quality out there. To the point had they not hijacked with there marketing in this thread I think I would have just placed a order. It's just really annoying. |
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