Tabless LiON Batteries

Ben Toogood

LiPo Batteries Are About to Be Replaced

LA Hover Bikes

Tabless LiOn FPV Batteries?

Joshua Bardwell

Can "Tabless" LiOn Replace LiPo Batteries?

Why Is This Tabless 21700 Is Better Than Molicel For High Discharge

Lithium Battery Cell Teardown

Conversation

with Gemini


Question:

I am considering using this battery on this page and building a 6S pack to be used for RC helicopters. Can you total the weight of 6 of these, consider the wiring (likely 10AWG for both pos/neg terminals), the balancer plug and the XT90 and see how much lighter it is than typical 6S 5000mAh lipos?

Tenpower 50XG (tabless) Specifications

          Brand                                TENPOWER
          Model                                INR21700-50XG
          Battery Type                         21700 Lithium-Ion (INR)
          Nominal Capacity                     5000mAh
          Minimum Capacity                     4950mAh
          Nominal Voltage                      3.6V
          Full Charge Voltage                  4.2V (max 4.25V)
          Discharge Cutoff Voltage             2.5V
          Max Continuous Discharge             40A (no temp cutoff) / 90A (75°C cutoff)
          Max Pulse Discharge                  140A (3 seconds)
          Standard Charge Rate                 0.5C (2.5A, CCCV)
          Max Charging Current                 15A
          Internal Resistance                  ≤4mΩ (AC 1kHz)
          Cycle Life                           ≥500 cycles (≥60% capacity retention)
          Operating Temperature                Charge: 0-45°C / Discharge: -20-60°C
          Cell Surface Temperature             Discharge up to 80°C
          Battery Top                          Flat Top
          Protected                            No (Unprotected Cell)
          Diameter                             ≤21.50mm
          Length                               ≤70.50mm
          Weight                               ≤71g
                          

Here's the math and the analysis using the Tenpower 50XG specs. Crucially, because these are true 5000mAh cells, you get a direct 1:1 capacity match to a standard 5000mAh LiPo.

  1. Custom 6S1P Tenpower 50XG Weight

    • Cells: 6 x Tenpower 50XG (Max 71g per cell) = 426g
    • Main Discharge Leads: ~15cm of 10AWG wire (positive/negative) = ~15g
    • Main Connector: 1 x XT90 plug = ~14g
    • Balance Lead & Plug: 6S JST-XH balance harness = ~10g
    • Assembly Materials: Nickel strips, insulation rings, tape, and heavy-duty PVC shrink wrap = ~15g

    Total Estimated Pack Weight: ~480 grams

  2. Comparison to Standard 6S 5000mAh LiPos: Since a standard 6S 5000mAh hobby LiPo typically weighs around 750g (ranging from 680g for low-C up to 800g+ for extreme 3D packs):

    Weight Saved = 750g - 480g = 270g

    The Takeaway:

    Even with the slightly heavier 5000mAh cells, you are still saving roughly 270 grams (about a 36% weight reduction) compared to a standard LiPo, but this time without sacrificing any capacity.

  3. Revised Helicopter Performance Outlook (Tenpower 50XG): The Tenpower 50XG specs change the game significantly for an RC helicopter compared to other Li-ion cells:
    • True 5000mAh Capacity: You aren't giving up flight time to save weight. In fact, because the helicopter is 270g lighter, the motor will pull fewer amps just to stay airborne. You can expect a notable increase in flight time compared to a standard LiPo.
    • Impressive Current Delivery: The 40A continuous (no temp cutoff) and 90A (with 75°C cutoff) rating is incredibly high for a 5000mAh Li-ion.
      • For context, 40A continuous on a 5000mAh pack is an 8C discharge rate, and 90A is an 18C rate.
      • While a hard-core 3D helicopter can still spike past 140A during aggressive pitch pumps (which hits the absolute ceiling of the 50XG's 3-second pulse limit), this cell is an absolute home run for sport flying, scale builds, or steady aerobatics.
    • Low Internal Resistance: At ≤4mΩ, these cells will suffer far less voltage sag under load than older-generation Li-ion cells, keeping your head speed more stable during flight.

Just remember to drop your ESC or telemetry low-voltage warning down toward 2.8V-3.0V per cell so you can actually utilize the full capacity without triggering an early auto-rotation!

Important RC Helicopter Considerations

While the weight savings are massive, you'll want to balance that against a few performance differences:

Current Draw (Amps) & Voltage Sag: The 50XG is rated for a massive 90A continuous discharge (with temperature cutoff) or roughly a continuous 10C rate. While they can handle brief bursts higher, standard pouch LiPos routinely push 150A to 250A+ continuous. If you fly aggressive 3D maneuvers, you will notice significant voltage sag and potential overheating. However, for scale flying, sport flying, or aerial photography, they excel.

Low Voltage Cutoff (LVC): Li-ion cells can safely pull down to 2.5V or 3.0V per cell under load, whereas standard LiPos shouldn't go below 3.5V. You will need to adjust your transmitter telemetry alerts or ESC cutoff thresholds so you don't trigger an early forced landing.

Bench Test Results: Tenpower 50XG (tabless)

40A/90A 5000mAh 21700

These tests only note my personal ESTIMATED ratings for these batteries at the time I tested them. Any battery that is "rewrapped" (not in its original factory wrap) can change at any time! This is one of the hazards of using these batteries so carefully research any battery you are considering using before purchasing.

Misusing or mishandling lithium-ion batteries can pose a SERIOUS RISK of property damage, personal injury, or even death. They should never be used outside of a fully protected battery pack and you use them at your own risk. Never exceed the battery's true continuous discharge rating (CDR), never let it get colder than 0°C or hotter than 60°C to help lower risk and extend cell life, and keep the plastic wrap and top insulating ring in perfect condition. Never use a battery that is physically damaged in any way.

Please read the report before asking any questions:

https://tinyurl.com/pa949zxv

18650/21700 Ratings & E-Scores and Recommended Batteries Tables:

The links are in my public Patreon pinned post: https://www.patreon.com/posts/pinned-post-137974946

I want to work for the community full time! If you feel what I do is worth a couple dollars a month and you would like early access to battery availability, battery and charger testing and news, and a say in what I test, then please consider becoming a patron and supporting my testing efforts: https://www.patreon.com/batterymooch.

Tenpower 50XG

Conversation

with Gemini


Question:

are all of the batteries on this page considered to be a "tabless" batteries?


Yes, all of the batteries listed on this page are considered to be "tabless" lithium-ion cells.

The category page you are viewing is explicitly filtered for Tabless Lithium Ion Batteries, and the specific models shown—such as the Ampace JP40, EVE 50PL, and TENPOWER 50XG—are all part of a newer generation of cylindrical 21700 cells designed with tabless architectures.

Why Are They Grouped Together?

In a standard cylindrical lithium-ion cell, the electrical current flows through a single metal "tab" welded to the copper and aluminum foils inside. This creates a bottleneck for electricity, causing high internal resistance and heat build-up under heavy loads.

"Tabless" design (popularized heavily by Tesla's 4680 format and now widely adopted in high-performance 21700 cells like the ones on your screen) removes that narrow tab. Instead, the edge of the foil is laser-slit into a series of tabs or left as a continuous strip that makes contact across the entire end of the roll.

What This Means For These Specific Cells:

Because they are tabless, these batteries are built for massive power delivery and ultra-high discharge rates without overheating. You can see this directly in their ratings on the page:

  • Massive current limits: The cells listed boast continuous discharge ratings anywhere from 50A to 90A (like the TENPOWER 50XG).
  • Lower internal resistance: They run significantly cooler than a traditional cell when pushed to their limits, making them ideal for high-drain applications like heavy-duty power tools, high-performance RC applications, or custom high-amp battery packs.

Question:

which of these batteries would be best to use to build a high performance 6s pack?

Building a high-performance 6S1P pack (22.2V nominal) for demanding RC applications like helicopters or high-power EDF jets puts an incredible strain on Li-ion cells. While tabless architecture makes all of these options viable, they are not all created equal when it comes to voltage sag under heavy load, total amp delivery, and capacity balance.

Here is how the top contenders from this page stack up against each other for a high-performance 6S build.

The Verdict: Which is Best?

  1. The Ultimate Performance Pick: Ampace JP40 (4000mAh)

    If your primary goal is sheer power delivery, minimal voltage sag, and keeping your motor RPMs completely stable during aggressive maneuvers, the Ampace JP40 is the clear winner for a high-performance build.

    The Math: While it drops your capacity down to 4000mAh compared to the 5000mAh cells, its internal chemistry is optimized purely for raw output.

    Discharge Rating: It handles 60A completely unrestricted (no thermal cutoff needed) and up to 70A with a temp cutoff, backed by a massive 140A 5-second pulse rating.

    Why it wins on performance: In a 6S1P configuration, the JP40 will hold its voltage significantly higher at the 50A-70A mark than any 5000mAh cell on the market. If you are flying a model that pulls quick, heavy bursts of power, this cell will feel closest to a traditional LiPo battery while still shedding a ton of pack weight.

  2. The Best Balanced Pick (Capacity + Power): Tenpower 50XG (5000mAh)

    If you want to maintain the maximum possible flight time while still pulling serious amps, stick with the Tenpower 50XG from our previous breakdown.

    The Math: You get a true 5000mAh capacity paired with an astonishing 90A temporary pulse/thermal rating (40A absolute continuous without a cutoff).

    Why it's a close second: For steady sport flying, scale flying, or continuous high-output sweeps (like an EDF jet or smooth aerobatics), it is an incredible cell. However, if you push it past 50A continuously or demand instant spike recovery, it will experience slightly more initial voltage sag than the lower-capacity JP40.

  3. The Budget Performance Pick: BAK 45D (4500mAh)

    If you are looking at the price-to-performance ratio, the BAK 45D is a fantastic middle ground.

    The Math: It splits the difference perfectly with a 4500mAh capacity and a rock-solid 60A continuous rating (with an 80°C cutoff).

    Why it's worth considering: At its sale price point, building a 6S pack out of these gives you a very low internal resistance (~3.4mΩ) and excellent thermal management for a fraction of the cost of premium cells.


Quick Comparison Table for a 6S1P Pack
Cell Model Pack Capacity Max Continuous Current Est. Pack Weight (Cells Only) Best For
Ampace JP40 4000mAh 60A (70A w/ temp cutoff) ~420g Maximum punch, lowest sag, aggressive flying
BAK 45D 4500mAh 30A (60A w/ temp cutoff) ~414g Great budget-friendly balance of power/capacity
Tenpower 50XG 5000mAh 40A (90A w/ temp cutoff) ~420g Maximum flight time, scale flying, smooth aerobatics
EVE 50PL 5000mAh 50A ~432g Alternative option for high-capacity endurance

Important Build Note for 6S Packs: Because you are assembling these in series to handle high-performance loads, standard nickel strip spot-welding will bottleneck your power.

To actually utilize the 50A+ capabilities of these tabless cells, you will want to build the pack using copper-nickel sandwich strips or heavy-duty pure copper busbars to keep connection resistance to an absolute minimum.

Resources

Note:

"Tested by Mooch" refers to the rigorous, objective lithium-ion battery testing conducted by John "Mooch" Muchow. Widely regarded as the industry authority in the vaping, flashlight, and custom electronics communities, his work exposes exaggerated safety ratings by finding the true Continuous Discharge Rate (CDR) and real-world capacity of batteries. Mooch's independent tests help consumers avoid unsafe batteries and get maximum performance out of high-drain devices. You can find his full safety guides, recommended cell rankings, and safety articles across his official testing hubs:

  • Official Reports: Access his comprehensive cell testing library on the E-Cigarette Forum Blog.
  • Tables & Updates: View his up-to-date lists of rated and recommended batteries on the E-Cigarette Forum Recommended Batteries Table.
  • Community Support: Access early testing news and support his efforts on the Battery Mooch Patreon.