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TB47 TB48 Battery Discharge

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Beginning page 20 of my manual, later on it states that every ten recharge cycles, to discharge the battery to a point where it will no longer turn on. Inspire 1 Pro User Manul v1.4 2017.12. Then recharge it. Discharge it either by a slow drain of powering up the aircraft while it sets there, or, in a rapid fashion by flying it until there is less than 5% remaining. This is to reset the calculation of battery capacity. And, in my mind, to help erase any 'memory' a cell may have.

It states the aircraft battery will be shut off automatically when the minimum point is reached.

Is this shutoff point reached by the circuit board within the battery? Or, a combination of it and the brains of the drone/remote controller?

If the battery, then why would this not work? Connect 2-3 12v light bulbs in series and connect that to the battery? Let it drain until it shuts off. One may have to try different light bulbs to attain a satisfactory discharge rate. Not to heat the battery much, if at all. And to do it on a timely fashion.

Also, after a default time of ten days, the circuit board will drain it down to 65% automatically over a couple days. Can I assume, this is a 'sweet spot' for this battery? And, it is better for short or long term storage not to have a fully charged battery? It mentions the battery can swell a bit if left fully charged.

Also, it mentions when the Battery Level Indicators reach 0%, "it can no longer be used". Is that a warning for us not to use it any longer? Or, does the circuit board shut it off and not allow any further use? I submit, the former is the case. And that would allow us to replace the actual battery and reuse the existing circuit board. Creating counts larger than 200 at some point.
 
Beginning page 20 of my manual, later on it states that every ten recharge cycles, to discharge the battery to a point where it will no longer turn on. Inspire 1 Pro User Manul v1.4 2017.12. Then recharge it. Discharge it either by a slow drain of powering up the aircraft while it sets there, or, in a rapid fashion by flying it until there is less than 5% remaining. This is to reset the calculation of battery capacity. And, in my mind, to help erase any 'memory' a cell may have.

It states the aircraft battery will be shut off automatically when the minimum point is reached.

Is this shutoff point reached by the circuit board within the battery? Or, a combination of it and the brains of the drone/remote controller?

If the battery, then why would this not work? Connect 2-3 12v light bulbs in series and connect that to the battery? Let it drain until it shuts off. One may have to try different light bulbs to attain a satisfactory discharge rate. Not to heat the battery much, if at all. And to do it on a timely fashion.

Also, after a default time of ten days, the circuit board will drain it down to 65% automatically over a couple days. Can I assume, this is a 'sweet spot' for this battery? And, it is better for short or long term storage not to have a fully charged battery? It mentions the battery can swell a bit if left fully charged.

Also, it mentions when the Battery Level Indicators reach 0%, "it can no longer be used". Is that a warning for us not to use it any longer? Or, does the circuit board shut it off and not allow any further use? I submit, the former is the case. And that would allow us to replace the actual battery and reuse the existing circuit board. Creating counts larger than 200 at some point.
This has been covered many times previously on the forum. Please do a search and you will find multiple threads regarding discharging/maintaining batteries etc.

LVC is built into the ‘smart battery’ itself to prevent over discharge of the cells.

Yes, you could use something like a 50w car headlight bulb etc (although the bulb will get very hot) to discharge down to LVC or simply use a device like Phantom angel.

 
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Beginning page 20 of my manual, later on it states that every ten recharge cycles, to discharge the battery to a point where it will no longer turn on. Inspire 1 Pro User Manul v1.4 2017.12. Then recharge it. Discharge it either by a slow drain of powering up the aircraft while it sets there, or, in a rapid fashion by flying it until there is less than 5% remaining. This is to reset the calculation of battery capacity. And, in my mind, to help erase any 'memory' a cell may have.

It states the aircraft battery will be shut off automatically when the minimum point is reached.

Is this shutoff point reached by the circuit board within the battery? Or, a combination of it and the brains of the drone/remote controller?

If the battery, then why would this not work? Connect 2-3 12v light bulbs in series and connect that to the battery? Let it drain until it shuts off. One may have to try different light bulbs to attain a satisfactory discharge rate. Not to heat the battery much, if at all. And to do it on a timely fashion.

Also, after a default time of ten days, the circuit board will drain it down to 65% automatically over a couple days. Can I assume, this is a 'sweet spot' for this battery? And, it is better for short or long term storage not to have a fully charged battery? It mentions the battery can swell a bit if left fully charged.

Also, it mentions when the Battery Level Indicators reach 0%, "it can no longer be used". Is that a warning for us not to use it any longer? Or, does the circuit board shut it off and not allow any further use? I submit, the former is the case. And that would allow us to replace the actual battery and reuse the existing circuit board. Creating counts larger than 200 at some point.
****Warning, Battery packs store tremendous energy and can release that energy very quickly resulting in tremendous heat. Wires and test leads can turn red hot immediately if shorted carelessly. The batteries themselves can be ignited and burn in a very dangerous chemical reaction. Know various chemistries of batteries, handling and fire precautions before doing more that the consumer presented (manual) processes. At very least, everyone should watch a video on a LiPo battery set to burn***

The recommended discharge is to get cells to low voltage. This allows for what is called "bottom balance". It might help to watch a YouTube video on battery bottom balance to understand you are equalizing cells based from a low voltage point to make each cell equal preventing unequal cells that end up holding reduced charge or cause other cells to make up for the deficiency.

The battery assembly has a BMS, battery management system. The minimum point should stop additional discharge of the battery. It is not foolproof but generally works.

The BMS determines the shut off point. The BMS also provides telemetry info from flight controller to remote to video output to app on tablet or phone connected to remote.

You can discharge the battery assembly to a storage level (usually around 50%. Instead of some easy answer, do a little research on LiPo battery maintenance. Understand cell voltage at minimum, storage and charge. Understand "C" rate or how much charge/discharge a battery pack can safely endure. It is not difficult to understand and will give you a lot of answers to your questions. Knowing how things work let you take command over those things. The lights or a sufficient wire wound resistor (compatible volt/amps) can be used to discharge batteries. You will need a connector for the battery and a voltmeter to ensure the proper stopping point. You could build or purchase a device that limits discharge...again online research and YouTube...lots of people do battery maintenance for RC and other hobby. The main concern here is the C rate...do not discharge batteries past this capacity, they overheat and will be damaged.

The BMS discharge is a storage voltage. As set by the manufacturer. You can debate their logic for where things are set or develop other strategy based on your studied knowledge of LiPo battery voltage and function.

LiPo batteries should not be run below a certain voltage. Occasionally it happens. Many LiPo battery chargers will not attempt to charge a low voltage battery pack. If the condition is not left too long, and the battery is not damaged too much, it is possible to give the pack a quick "jump start". Applying voltage to the pack for a short time to simply get the voltage into the area the charger recognizes as a chargeable battery. Again, research and YouTube videos will outline the process. It appears that certain manufacturers build careful product design to ensure all business is directed directly to them. The Inspire battery is such a product. There are a lot of people working on solutions to battery solutions...some good and some not so good. Again some research will be necessary to determine what path you want or are capable of pursuing. Some people are offering consumer solutions, others offer a DIY approach.
 

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