Header Overview

  • LiPo-batteries do not have any memory effect. Never fully discharge LiPo-batteries as it will permanently damage the batteries.
  • Do not store the batteries fully charged. It will lead to a shorter life time of the battery. 
  • Whenever possible store the batteries half charged at storage voltage of 11.4 V and only charge them completely shortly before the next flight. 
  • Secure all connectors against short circuits before transporting them and store them only in special LiPo safe bags or LiPo safe cases.
  • The capacity of Li-Po batteries drops dramatically if the temperature is below 5° C.


Please read below safety instructions and warnings carefully before charging or using batteries

Lithium Polymer batteries safety instructions and warnings

AscTec Li-Po batteries have two separate leads. The lead with the BLACK connector and BID-chip is for balancing only. The second longer lead (RED AND BLACK) is for charging and discharging or the power source for your aircraft.  

  • You must read these safety instructions and warnings before using or charging your batteries.
  • Lithium Polymer batteries are volatile. Failure to read and follow the below instructions may result in fire, personal injury and damage to property if charged or used improperly.
  • Ascending Technologies cannot assume any liability for failures to comply with these warnings and safety guidelines.
  • Always keep a Class D (ABC-Powder) fire extinguisher nearby your battery charging/discharging and storage area. The battery charging/discharging and storage area should be free from any materials which can catch fire such as wood tables, carpet, or gasoline containers. The ideal surface for charging and storing LiPo batteries is metal, concrete or ceramic.
  • By purchasing this battery, the customer assumes all risks associated with lithium batteries. If you do not agree with these conditions, return the battery immediately before use.

General Guidelines and Warnings

  1. Use our recommended Lithium Polymer charger only. Do not use a NiCd or NiMh charger - Failure to do so may cause a fire, which may result in personal injury and property damage. It is crucial that all cells in a LiPo battery maintain the same voltage across all cells at all times.
  2. Never charge batteries unattended and monitor the charging process. When charging Li-Po batteries you should always remain nearby to monitor the charging process and react to potential problems that may occur.
  3. Some Li-Po chargers on the market may have technical deficiencies that may charge the Li-Po batteries incorrectly or at an improper rate. It is your responsibility solely to assure the charger you purchased works properly. Failure to do so may result in fire.
  4. If at any time you witness a battery starting to balloon or swell up, discontinue the charging process immediately. Disconnect the battery and observe it in a safe place for an appropriate period of time. Continuing to charge a battery that has begun to swell will result in fire. Likewise, never use a battery if you find it swollen or ballooned.
  5. NEVER continue to charge LiPo batteries if the charger fails to recognize full charge. Overheating or swelling of the LiPo cells is an indication of a problem and the battery should be disconnected from the charger immediately and placed in a fireproof location.
  6. Since delayed chemical reaction can occur, it is best to monitor the battery as a safety precaution. Battery monitoring should occur in a safe area outside of any building or vehicle and away from any combustible material. Always charge LiPo batteries in a fireproof location.
  7. Shorting with the wire leads can cause fire! If you accidentally short circuit the wires, the battery must be placed in a safe area for observation for an appropriate period of time. Additionally, if a short occurs and contact is made with metal (such as rings on your hand), severe injuries may occur due to the conductibility of electric current.
  8. A battery can still ignite even after a longer period time.
  9. In the event of a crash, you must remove the battery for observation and place in a safe open area away from any combustible material for an appropriate period of time.
  10. Never store or charge a battery pack inside your car in extreme temperatures, since extreme temperature could cause fire.

Before You Charge

  1. Make a visual inspection of the pack. Look for any damaged leads, connectors, broken heat-shrink, extreme swelling of cells, or other irregularities. Do not use it if you find any of the above issues with your pack.
  2. If any damage to the pack or leads is found, or the voltage is significantly less for your pack than specified below, do not attempt to charge or fly the pack; contact Ascending Technologies directly as soon as possible.


  1. Never charge batteries unattended.
  2. Charge in an isolated area, away from other flammable materials. Use the AscTec LiPo safe-bags or a non-flammable case for charging.
  3. Let the battery cool down to ambient temperature before charging.
  4. Do not charge batteries packs in series. Charge each battery pack individually. Failure to do so may result in incorrect battery recognition and charging functions. Overcharging may occur and fire may be the result.
  5. Be sure you use the right connector for all charging. There are two sets of lead wires on this battery. The one with the BID-chip is always used exclusively for balancing the cells. The one with the green connector is used for charging.
  6. When selecting the cell count or voltage for charging purposes (not needed with the ROBBE charger), select the cell count and voltage as it appears on the battery label. Selecting a cell count or voltage other than the one printed on the label can cause fire. As a safety precaution, please confirm the information printed on the battery is correct.
  7. You must check the pack voltage before charging after flight. Do not attempt to charge any pack if the voltage per cell is less than 3.3V. Do not charge a 3 cell pack if below 9.9V.
  8. You must select a charge rate current that does not exceed 1C (1C = one time the capacity of the battery). A higher setting will reduce the battery life span and may cause fire. The below examples are calculated at 1 x capacity of pack.
    Example 1: a battery with 1800 mAh must be charged at or below 1.8 A  
    Example 2: a battery with 6250 mAh must be charged at or below 6.2 A


To reach the maximum lifespan of your AscTec Li-Po batteries, please don‘t discharge them with high loads for the first few flights. Do not discharge a battery to a level below 3.5V per cell under load. Deep discharging a battery cell below 3.5V can reduce battery performance or even destruct them.

First Flights

We recommend 3-5C (1C = one time the capacity of the battery) max average discharge for new batteries. Also, be extremely careful not to deep discharge new packs (Packs should NEVER be deep discharged at any time, but deep discharging on the first flight will ruin the battery permanently before you are able to use it properly. See “Caring for Battery” below).

Storage & Transportation

  1. Store batteries at room temperature between min. 15 °C and 25 °C (40 and 77 degrees F) for best results.
  2. Do not expose battery pack to direct sunlight (heat) for extended periods.
  3. When transporting or temporarily storing in a vehicle, temperature range should be greater than 0°C but no more than 60°C (20 degrees F but no more than 150 degrees F).
  4. Never leave the LiPo batteries on a full charge for more than 2-3 days. For longer intermissions you need to discharge the batteries to 11.4 V (3.8 V per cell) for safe storage until you are ready to use the battery again. Recharge the batteries right before the next mission.
  5. Storing batteries at temperatures greater than 60°C (140 degrees F) for extended periods of time (more than 60 minutes) may cause damage to the battery and become a fire risk.

Caring for Batteries

  1. Charge batteries with a good quality Lithium Polymer charger. A poor quality charger can be dangerous. Use preferably the Ascending Technologies recommended chargers.
  2. Set voltage and current correctly (failure to do so may cause a fire).
  3. Please check pack voltage after charging. It is shown on the charger display.
    Example 3-Cell: 12.3 – 12.6V
  4. Do not discharge batteries to a level below 3.5V per cell under load. Deep discharge below 3.5V per cell will deteriorate battery performance.  
  5. Avoid puncturing the battery cells. Punctured cells may cause fire.

Operating Temperatures

  • Charge: 10°C to 45°C (45 to 110 degrees F)
  • Discharge: 0°C to 60°C (32 to 140 degrees F)
  • Recommended for flying: 25°C to 40°C (75 to 105 degrees F)
  • Storage temperature: 15 °C to 25 °C (40 and 77 degrees F)

Battery Life

Batteries that lose 20% of their capacity must be removed from service and disposed of properly.


For proper treatment, recovery and recycling, please take these products to designated collection points, where they will be accepted on a free of charge basis. Alternatively, send the battery for disposal back to Ascending Technologies. Disposing of this product correctly will be help to save valuable resources and prevent any potential negative effects on human health and the environment which could otherwise arise from inappropriate waste handling. For disposal please discharge the battery to 3V/Cell or below, making sure output wires are insulated, then wrap battery in a bag for disposal.

Product Warranty

Product warranty is limited to original defects in material and workmanship. Warranty does not cover collateral damage. Due to the nature and use of this product there is no term warranty. Misuse, abuse, incorrect charging, failure to comply with the above warnings and guidelines, and other inappropriate use of this product are not covered under warranty.