UK distributor and RC manufacturer RadioC has its newest Drone Lab CHAOS Edition lipo packs out on the market. The Drone Lab series is specifically designed for use in race quads with highest power demands. This review looks at the 1500 mAh version of the CHAOS 4 cell pack.
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Some competitors almost started a contest on the „most beautiful“ lipo. Well RadioC is taking the other route, aware of the fact not to win any design prices. That said: The Drone Lab packs come in a simple black shrink wrap. A blue-ish sticker on the front – that’s it. As a purist I kind of like that approach. The new CHAOS Edition features a big „CHAOS“ lettered on top of the old sticker. On the back you find the usual safety instructions.
The Drone Lab CHAOS Edition 75-150C pack is a standard 4S1P config flight pack for high power use. A foam layer on the front and back provides extra impact protection on the cell edges.
Build Quality: Very good. Pack feels very well made on the outside. Connection terminal looks solid.
Plugs: The Drone Lab pack comes with standard black XT60 connectors* equipped.
Cables: RadioC 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 rather short (4,5 cm) which is a benefit in terms of getting them out of the prop-range on the aircraft. Main power line is coming out of the top, balancing wires are connected at the bottom.
(Click to enlarge.)
|Type||Drone Lab 75-150 C|
|Cell chemistry||Lithium Polymere (LiPo)|
|Cell type||Drone Lab CHAOS Edition|
|Max. Charge Current||5 A|
|Max. Discharge Current
ca. 168 grams
|90 x 34 x 27 mm
91 x 33 x 28 mm
|Note||This battery has been directly donated by the manufacturer / distributor for review purposes.|
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||4.0||4.0||3.8||3.8||15.6|
|After second charge||4.4||3.1||4.7||4.0||16.2|
|After third charge||4.2||4.2||4.8||3.8||17.2|
|After fourth charge||3.9||4.1||3.7||3.9||15.6|
CV-Phase is short on this cell type. Balacing in normal mode took 1:31 min. Cell drift during charge was unobtrusive. This is for 1C charge (1,5 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 1163 mAh. This is 77.5 % of nominal capacity. A solid value.
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||3.735 V||3.728 V||3.727 V||3.732 V||14.921 V||3.73 V|
Just looking at average values the DroneLab pack performs good. All cells stayed well above 3,7 V on average. An average value above 3.75 V / cell can be considered very good.
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||3.515 V||3.495 V||3.529 V||3.563 V||14.102 V|
|End of 35 C||3.531 V||3.523 V||3.541 V||3.562 V||14.158 V|
|End of 20 C||3.374 V||3.354 V||3.276 V||3.555 V||13.538V|
|End of 30 C||–||–||–||–|
Voltage sag is relatively high on the DroneLab 1500 mAh pack. Cell voltages went below the 3,5 V/cell benchmark on all first load cycle.
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||0.0343 V / s||0.036 V / s||0.037 V / s||0.0309 V / s||0.1382V /s|
Strong voltage drops correspond to high recovery rates within five seconds after the load impulse is cut-off. Recovery is made to a normale level rather quick.
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 2.64 mΩ average per cell indicates a „true“ C-rating of around 39 C (58.4 A). This is on the conservative side and represents a current draw that will make the pack last for a long time. See load testing for further categorization. This categorization helps explaining the heavy voltage sags as the first load impulse (75 A) and the second cycle (52,5 A) go way beyond what should be demanded from this pack (even if both pulses a within the claimed specs).
Cell drift under load
|Discharge Phase||50 C||35 C||20 C||30 C|
|Max Cell drift (V)||0.22 V||0.039 V||0.102 V||–|
Cell drift is strong especially on first discharge pulse (50 C). Medium loads are represented by usually small cell drift.
Key Temperature Facts
Max. temp during discharge was around 61,4 °C on top of pack. This would have resulted in a cut-off, but cell voltage rule has been applied just a little before that. Note that heating of stressed LiPo packs will continue for some more time even when load is cut. This pack has to be cooled down actively immediately as temperature was on its way to 70°C.
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 quick. The battery provided 1156 mAh (77,1 %) during the 25 C discharge.
Comparison of different reviewed 1500 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 1137 mAh. This is 75.8 % of nominal capacity. Still a good value. In patter 2 testing 1160 mAh (77.3 %) could be used until first cell reached cut-off voltage.
The following charts give an overview of all tested packs in the 1500 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 DroneLab 4S CHAOS Edition 1500 mAh 50-100 C battery is a usual sized pack with a capacity to weight ratio of 8.92 mAh/g. The measurements are standard for the 1500 mAh class. Overall build quality is good. The design is best described as modest. Perfect for everybody looking to put a black pack on there full carbon style mini quad! Average voltage stability is very good on this pack. Nevertheless, one should be aware of the relatively strong voltage drop to the end. Once cell voltage goes below 3,5 V its time to come in for landing quiet fast. Usable cell capacity under real-life flight setting is very good. Ohm-matching is okay, I noticed quiet some cell drift unter high loads. As most of the packs in this performance class the C rating is a little over the top. If long term continuous currents are needed, make sure to stay within the real rating of around 39 C. Nevertheless, the pack is able to handle short currents spikes way above this without any problems. I would recommend to use this packs for continuous loads up to 58 A maximum. Notice that under this circumstances heat generation of the pack will very be strong (assure proper cooling!!!). Looking at the overall results the CHAOS edition is a real upgrade over the standard DroneLab cells. Part of it’s great performance is bought by having some extra mAh as a buffer, but being labeled as a 1300 mAh pack. Looking at weight and charger readings I would think this battery is closer to a 1600 mAh pack in reality, but I well keep judging based on the marketing value. (As long as you get more than advertised!) Pricing of the DroneLab 4S CHAOS Edition 1600 mAh 75-150 C battery is still very hot. For around 24 € this pack is highly competitively priced and almost 10 Euros cheaper than some of its competitors products. The great price might even let some buyers overlook the rather strong cell drift. Quality wise the DroneLab CHAOS edition continuous to make a good stand for it’s really low price tag. At the moment the 1500 mAh version is even cheaper than the 1300 mAh product. So if you can fit it on your rig, go for the 1500 mAh version at a great price!
Other packs of this line up tested: