Charging/Storing LiHV Batteries

 

Charging Batteries

Charging LiPo (Lithium Polymer) High Voltage batteries requires careful attention to safety protocols and adherence to manufacturer guidelines. These batteries, often denoted as LiHV, possess a higher nominal voltage compared to standard LiPo batteries. It is crucial to utilize a dedicated LiPo charger that supports the higher voltage range to prevent overcharging and potential damage. When using the charger, the user should always check that HV has been activated before charging your battery. Charging a LiHV battery on the LiPo setting will cause the battery to be very undercharged.

 

Click this link to watch the how to video from WISPR : https://www.youtube.com/watch?v=I9lGah_KPqA&t=7s

To change the settings from LiPo charge to LIHV charge, hold both of the two arrow buttons down at the same time on the charger. This will change the charging process to HV and will allow you to charge batteries at high voltage.

 

Now that the correct settings are configured for the battery type, the amperage should be set to 20A for maximum charging capacity.

To adjust the amperage:

  • While on the charging information screen, lightly press the start button, allowing navigation to other screen options for adjustments. The selected section will blink, indicating it is active and can be adjusted.

    • Continue pressing the start button until you reach the amperages column. Once there, use the up arrow above 'status' to increase the amperage to 20.0A. Confirm this setting by lightly pressing the start button.

The settings are now correct, and the battery is ready for charging.

  • Connect the battery's XT90 connector to the charger's XT90 port (yellow connector).

  • Attach the balance port from the battery to the corresponding balance port plug on the battery charger (white plug).

  • Press and hold the start button until the screen blinks and you hear 3 beeps. You can release the start button at this point. Press the start button lightly once again to initiate the charging process. (Ensure proper connection of the XT90 plug and balancer for these steps to function correctly).

 

When initiating the charging process, there are three distinct methods available: Balanced Charge, Fast Charge, and Storage Charge.

  • Balanced Charge - For maximum health, you should always balance charge your batteries. This is also why your battery has a second plug. This second plug is called the “balance plug” and is used by your charger to individually monitor and balance charge each cell. Balanced Charge is the recommended way to charge your batteries at all times.

  • Fast Charge - This mode directs the charger to only complete the first charging phase, constant current (CC) charging. The charger applies a high enough voltage to cause current to flow into the battery, up to the max current you've set. This will mostly charge the battery, but there will still be some unused capacity with this mode.

  • Storage Charge Storage charge is used when batteries will not be used for a period of time. (This will be talked about below)

 

 

 

 

Charging Tips

  • Never charge Batteries that are hot to the touch (above 100° F). DO NOT handle Batteries until they are cool.

  • User should Always set the charger to the proper cell count and/or voltage listed on Batteries’ labels.

  • User should Always set the charger to the amp charge rate as listed on Batteries’ labels. The charger should never be set to charge Batteries at a rate greater than 1C (One (1) times the capacity of Batteries in amp hours) unless another C rate is specified in the manufacturer’s product documentation, or the rate is preset as part of a specific battery and charger combination. DO NOT alter the charge rate once charging has begun.

  • Never overcharge Batteries beyond the capacity listed on Batteries’ labels.

  • Never overcharge batteries over their rated maximal voltage (4.35V/cell for LiPo). –

  • Use a suitable and good quality charger. We always recommend using the charger provided by WISPR when charging your batteries to ensure quality.

  • When charging, please make sure the surroundings are clean.

  • Don’t charge without monitoring.

  • Stop charging timely when the battery is fully charged. Do not connect the charger and the battery for a long time when the battery is fully charged.

 

 

 

Storing/Discharging Batteries

 

Storage Mode should be implemented when the battery or batteries are anticipated to remain unused for a 24 hour or greater period. Employing this mode is integral for maximizing battery performance and extending their overall lifespan.

Ensuring the long-term health and safety of LiHV batteries mandates a crucial step: discharging them before extended storage periods. Set the charging mode to 'Storage Charge' and adjust the amperage if needed. You may Storage Charge on any Amps, depending on how fast you would like it to discharge. Change volts to the prescribed 'storage voltage' range of 3.8 to 3.85 volts per cell. This precautionary measure safeguards the batteries' well-being by bringing them to the recommended storage voltage before extended idle periods.

One primary concern is the potential for the battery voltage to drop below a safe threshold, which can result in cell damage and compromise the battery's overall performance. Moreover, stored batteries with a high charge are more susceptible to self-discharge, potentially leading to over-discharge and permanent damage. To prevent these issues, use the chargers’ storage charge function to bring the battery to the appropriate storage voltage. This practice mitigates the risk of safety hazards associated with overcharging or discharging beyond safe limits.

 

As said above, change charging modes (either from Fast Charge or Balance Charge to Storage Charge) to prepare your battery to be stored safely. Ensure your battery is connected to the charger as normal and hold down start button as you would normally until you hear the three beeps. Once the beeps are heard, lightly press the start button again to begin discharge.

 

 

DISCHARGING Tips

  • Never allow the temperature of Batteries to exceed 140° F during discharge. *Adequate cooling for Batteries is required, especially when discharging at or near maximum rates.

  • Never discharge battery to a level below 3V per cell under load.

  • Batteries which are used for Unmanned Aircraft system, the recommended cut off voltage is 3.5V per cell.

  • Never leave battery unattended during the discharge process. During the discharging process, the user should monitor the process constantly and react to potential problems that may occur.

  • In case of emergency, discontinue the process immediately, disconnect the battery, place it in a safe area, and observe it for approximately one hour. This may cause the battery to leak and the reaction with air may cause the chemicals to ignite, resulting in a fire. A safe area should be outside of any building or vehicle and away from any combustible materials. A battery can still ignite even after one hour.

  • The user needs to check the condition of the battery before using it or discharging it. Stop using it if user found the cells are not balanced or cells are puffing or weeping.

 

 

What can the logs tell us?

Flight logs can be pulled and evaluated by our team. This allows us to inspect the volts, how much current was pulled and also how many mAH were available when the drone was taken off and how many were used. When charging the battery back up (if number of mAH are noted) this can tell how many mAH it took to charge the battery completely up and aid in determining whether the battery received a complete recharge and provides insights into its overall performance.

 

 

To learn more about our batteries visit our FAQ Battery Page: https://wisprsystems.atlassian.net/wiki/spaces/CS/pages/106659841