Battery review: Dinogy Graphene 2.0 4S 1800 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 1800 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, that 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 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 via iCharger 406B at 40°C pack temperature
|Cycle||Cell 1||Cell 2||Cell 3||Cell 4||Total|
|After first charge||4.9||5.2||4.9||5.2||20.0|
|After second charge||4.9||5.0||5.0||5.5||20.4|
|After third charge||5.0||4.9||5.0||5.1||20.0|
|After fourth charge||4.9||4.8||4.9||5.0||19.6|
CV-Phase is short on this cell type. Balancing in normal mode took 2:06 min. Cell drift during charge was unobtrusive. This is for 1C charge (1,8 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 1323 mAh. This is 73.4 % 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||3.734 V||3.732 V||3.730 V||3.730 V||14.926 V||3.731|
Just looking at average values the Dinogy pack performs well. All cells stayed above or at 3.73 V on average. An average value above 3.73 to 3.75 V / cell can be considered very good in this class.
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||3.51 V||3.508 V||3.519 V||3.552 V||14.089 V|
|End of 35 C||3.512 V||3.513 V||3.52 V||3.536 V||14.081 V|
|End of 20 C||3.281 V||3.28 V||3.264 V||3.289 V||13.114 V|
|End of 30 C||–||–||–||–||–|
The average cell voltage stability on the Dinogy pack can be considered very good. No cell fell below the benchmark threshold of 3.5 V 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 [V/s]||0.027||0.027||0.0263||0.022||0.1035|
Excessive voltage sag isn’t a problem for this battery. Recovery rates after current pulses are decent, too.
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 2.54 mΩ average per cell indicates a “true” C-rating of around 36.2 C (65.2 A). A very good value. This calculation is on the conservative side and represents a current draw that will make the pack last for a long time. The pack had no problems delivering during high C discharge pulses. Cell matching is almost perfect on this pack.
Cell drift under load
|Discharge Phase||50 C||35 C||20 C||30 C|
|Max Cell drift (V)||0.019 V||0.035 V||0.028 V||–|
The Dinogy Graphene 2.0 4S 1800 mAh 70 C has a very low drift during main discharge phase. Even to the very end of the cycle cells drift is almost neglect-able.
Key Temperature Facts
All temperature probes reported values below cut-off point at 58°C. Max. temp during discharge was around 54.9 °C on top 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.
Cut-Off /warning value for this battery should be chosen 3.5 V minimum. After this point voltage drops very quick. The battery provided 1318 mAh (73.2 %) during the 25 C discharge. A great result.
Comparison of different reviewed 1800 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 1337 mAh. This is 74.3 % of nominal capacity. A good very value. In patter 2 testing 1353 mAh (75.2 %) could be used until first cell reached cut-off voltage. Very good again!
The following charts give an overview of all tested packs in the 1800 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 1800 mAh 70C battery is a usual sized pack with a decent capacity to weight ratio of 8.95 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. 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 testes within the 1800 mAh class so far. Cell matching is almost perfect on this pack, good job! The rating of 70C is a little over the top, of course. I would rate this pack at still very solid 36 C continuous. This allows you to pull around 66 A without having to worry about the packs health too much. You would have to punch out most of the smaller quads pretty hard to get that kind of load on a constant basis. As you can see in the dynamic loads higher current spikes are handled well, too. For around 37 € this pack is certainly not the cheapest battery you can buy – but also not the most expensive. On the other hand the Graphene 2.0 1800 mAh version is the best battery in this class I have reviewed so far. That’s not only true for performance, but also for overall product quality. In the end about 37 euros are still a fair price for a battery pack of this performance level.
Other packs of this line up tested: