Battery review: Dinogy Graphene 2.0 4S 1300 mAh 70 C
After reviewing the very promising prototype of the new Dinogy Graphene 2.0 packs, the time has finally come and I received samples of the final battery product. This review is looking at the 1300 mAh version of the all new Dinogy Graphene 2.0 4S 70 C pack.
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The final version of the Dinogy Graphene 2.0 pack looks a little different than the prototype tested earlier. The black shrink wrapping has been switched for a light grey one. Also the graphic sticker has been re-done, looking a lot more professional now. I am very happy to see, though, they decided to keep the cool looking, red, honey comb-style materials on the sides. On the back you now find a sticker that provides all the important information how to handle the battery. I really appreciate to see this stuff printed onto the pack. A lot better than giving out a small piece of paper as many other manufacturers tend to do. The packs come in a high quality card board box with a foam layer on the bottom. The pack itself is packed in bubble wrap. Also it is made sure by a little piece of foam that the XT60 connector stays in place and can’t damage the pack during transport.
The Dinogy Graphene 2.0 70 C pack is a standard 4S1P config flight pack for high power use. It utilizes the new generation graphene cell chemistry. An extra layer of carbon particles is added to minimize internal resistance and hence maximize possible current draw.
Build Quality: Very good. Pack feels very well made on the outside. Connection terminal looks solid. The read honey-comb materials feels like it offer good protection on the sides.
Plugs: The Dinogy pack comes with standard XT60 connectors equipped.
Cables: L&E uses 12 AWG wires on this packs. The high flexible silicon layer is rated up to 200°C. Cable length is about 8 centimeters.
Balacing plugs: Standard XT-system. Balance wires are very short (3 cm) which is a benefit in terms of getting them out of the prop-range on the aircraft. Main power line and balancer wires are both connected to the top of the pack.
The battery followed the standard break-in-process: The pack is charged at a rate of 1C until CV-phase ends with current of 1/10C. The break-in phase consists of four charging cycles at 1C and four corresponding discharges at 1 C / 4C / 10C and 20 C.
Anomalies: No anomalies during break-in.
Internal resistance measurements during break-in phase
|Cycle||Cell 1||Cell 2||Cell 3||Cell 4||Total|
|After first charge||7.2||7.1||6.8||6.8||27.9|
|After second charge||6.8||6.7||7.0||6.7||27.2|
|After third charge||6.2||6.3||6.8||6.5||25.8|
|After fourth charge||6.0||6.1||6.4||6.2||24.7|
CV-Phase is really short on this cell type. Balancing in normal mode took only 1:18 min. Cell drift during charge was unobtrusive. This is for 1C charge (1,3 A).
The main part of this battery test will consists of different load test settings showing the battery performance. Constant load testing is used to judge the advertised C-ratings as well as look at cell drift under high loads. We also check on internal resistance once more. Next up is the dynamic current test, which simulates a “real” flight with changing (=dynamic) loads. For test methodology please check the dedicated methodology page!
Constant Load Testing
Constant load testing follows a certain load pattern of different constant currents. Base load is 10 C. Current pulses at 50 C, 35 C, 20 C and 30 C are maintained for time intervals between 10 and 20 seconds. For more details please refer to the test methodology page.
During this test the pack delivered 964 mAh. This is 74,2 % of nominal capacity. A very good result.
Average cell voltages
The following table lists the average voltages per cell, of the total pack, as well as the averaged value per cell as fraction of total voltage during phase of active load.
|Cell 1||Cell 2||Cell 3||Cell 4||Total||Average per cell|
|Avg. Voltages||3.738 V||3.745 V||3.745 V||3.746 V||14.974 V||3.743 V|
Just looking at average values the Dinogy pack performs good. All cells stayed well above 3,7 V on average.
Exceptionally interesting when testing a battery under a constant load for a longer period of time: the lowest voltage per cell just before load impulse is disabled. On top, you should have look at voltage recovery rate, that is: how fast do cell voltages rise again once load impulse is cut.
|Phase||Cell 1||Cell 2||Cell 3||Cell 4||Total|
|End of 50 C||3.526 V||3.545 V||3.563 V||3.589 V||14.223 V|
|End of 35 C||3.524 V||3.537 V||3.549 V||3.546 V||14.173 V|
|End of 20 C||3,322 V||3.388 V||3.382 V||3.402 V||13.495 V|
|End of 30 C||–||–||–||–||–|
The average cell voltage stability on the Dinogy pack can be considered very good. No cell dropped below 3,5 V benchmark during the first two current pulses.
Average voltage recovery per second
Those values are specific to the test setting and not valid for the pack in general! Still they allow an estimated guess about how fast voltages rise again after current spikes.
|Cell 1||Cell 2||Cell 3||Cell 4||Total|
|Avg. Recovery||0.0388 V / s||0.0369 V / s||0.0341 V / s||0.0297 V / s||0.1395 V /s|
The pack shows low voltage drops and fast recovery rates when switched from current pulse to base load.
IR measurement is conducted using the four current pulses. Resistance for each cell is calculated in all four discharge phases. Shown values are averaged to cancel out different temperature points due to different discharge states during measurements.
Interpretation: The internal resistance of 3.01 mΩ average per cell indicates a “true” C-rating of around 40 C (50.9 A). This is on the conservative side and represents a current draw that will make the pack last for a long time. The pack had absolutely no problems delivering during high C discharge pulses. The cells seem to be matched good – cell 1 lags a little behind, though. Constant performance of 40 C is really (!) solid in this capacity class.
Cell drift under load
|Discharge Phase||50 C||35 C||20 C||30 C|
|Max Cell drift (V)||0,023 V||0,04 V||0,025 V||–|
Cell drift is very low on this Dinogy battery. Even to the end of the discharge cycle the cells stick closely together!
Key Temperature Facts
All temperature probes reported values below cut-off point at 58°C. Max. temp during discharge was around 52.3 °C on side of pack. Note that heating of stressed LiPo packs will continue for some more time even when load is cut.
The following chart shows all reviewed LiPos in the same product segment for direct comparison of performance. Higher values under load are better.
Constant 25 C Discharge
Pretty much a standard benchmark in the LiPo industry.
The recommended cut-off at 3.4 V / cell is a little optimistic. You would have to land immediately when hearing your buzzer going off in this setting. Cut-Off /warning value for this battery should be chosen 3,45 – 3,5 V minimum. After this point voltage drops very quickly. The battery provided 961 mAh (63,8 %) during the 25 C discharge. A very good value again.
Comparison of different reviewed 1300 mAh batteries under 25 C load.
Dynamic Load Testing
The dynamic load testing setting consists of two separate discharge scenarios that have been developed of two different real-life FPV flights. Pattern one represents a high speed low proximity flight around the open field with some hovering to the end. Average load is around 22 A. Second pattern is a free-style flight around trees in the park with some current spikes near 70 A. Average load on this flight is around 13 A due to longer floating periods.
During the test of pattern 1 the pack delivered 966 mAh. This is 74,3 % of nominal capacity. A very good result. In patter 2 testing 962 mAh (74,0 %) could be used before first cell reached cut-off voltage.
The following charts give an overview of all tested packs in the 1300 mAh class so far.
The last chart of this review sums up the usable capacity during all four load scenarios. Please note that this is only the capacity consumed by the electronic load! There are losses due to heating of the pack, which could be approximated (see testing methodology page). All four tests are cut when any cell goes below cut-off voltage of 3,3 V (or pack goes above 58 °C on any of the three probes). If you would push further and go down to 3,0 V/cell you will be able to squeeze out some mAh more, but at the cost of excessive heat generation and shortening of pack life-span. This value will most likely differ from what you get when flying on a quad as most people don’t monitor voltage on a per cell basis and therefore don’t even notice if voltage drops below 3,3 V/cell during punsh-outs (what’s not necessarily a good thing, though). For comparison, used capacity until 3,3 V/cell is reached is the base line in all battery reviews on Drone-Zone.de.
The all new Dinogy Graphene 2.0 4S 1300 mAh 70C battery is a usual sized pack with a capacity to weight ratio of 8.44 mAh/g. As other graphene enabled packs this battery tends to be just a little heavier than a “standard” lipo. Build quality of this battery is excellent. The pack is rectangular shaped and keeps it shape under every load situation. No puffing what so ever! I personally like the new design combining the light grey with the red honey-comb reflector materials at the sides. Voltage stability is great on the final Graphene 2.0 version. The pack managed to beat the prototype in every single aspect of testing. That’s great news, as some of the feedback seems to have been incorporated into the final product. Cut-off should be chosen at 3,45 V / cell minimum. The sticker on the pack tells you 3,4 V/ cell, but this would mean to cut of throttle immediately after you hear your telemetry or buzzer complaining. Usable battery capacity is the best of all packs tested within the 1300 mAh class so far. Cell matching has improved a little over the prototype, Dinogy is going in the right direction here. The rating of 70C is a little over the top, of course. I would rate this pack at still astonishing 40 C continuous. This allows you to pull around 51 A without having to worry about the packs health too much. An incredible value and nothing you would ever have thought of two or three years back when talking about 1300 mAh class batteries. As you can see in the dynamic loads higher current spikes are handled well, too. For around 31 US-$ this pack is certainly not the cheapest battery you can buy. On the other hand the Graphene 2.0 is one of the best batteries I have reviewed so far. That’s not only true for performance, but also for overall product quality. Plus graphene enabled packs tend to be a little more expensive still. In the end 31 bucks is a very good deal for this pack.
Other packs of this line up tested: