Batt discharge test station, Shock your Lipo.

[FLY BOY]

Greetings fellow flyers from the Pacific NW,

Just a quick tip on batt testing and draining. Today I went to the field with 6 fully charged batts. Really windy today so I only flew once, For that was all that was needed to say, to windy to fly today as my Dynam SU26 had a rough landing even with a Hobby Eagle Gyro on board. So I ended up at home with 5 fully charged batts. I simply took a spare motor,esc, and receiver, mounted it all on a flat board and guala! Batt drain and test station. 
 Just plug in with transmitter on like its in a plane, plug in your batt checker into its lead and throttle up. With a 12x8 prop dont take but 5 minutes to drain a fully charged batt and I get to monitor the batt with the checker. I can see all the cell voltage while under load, and watch the performance of the batt to. Then when I see that it is drained enough for storage, just throttle down and store the batt. 

No more hanging around the batt charger in discharge mode, or storage mode for 5 hrs. I'm done with that.
If your TX has a timer, you can put that into use to during the drain and test as well.

Happy Landings from the Pacific NW, Time is money.

[hick20]

RE: batt discharge test station

Thanks for the tip,
give us more great tips in future as well.

[FLY BOY]

RE: batt discharge test station

PRE SHOCK YOUR LIPO:

One thing that I have noticed about Lipo batts, They always seem to charge better and faster after that first flight of the day. So as an experiment, I took 3 Lipos and put them on the charger FRESH OUT OF STORAGE. They were 4s 3000mah batts.
It took a little over an hr to Balance charge each one. If you have one charger, thats 3+ Hrs sitting around and waiting.

Then I took the same 3 Lipos FRESH OUT OF STORAGE, hooked them up to my batt drain and test station.
Ran each batts at full throttle on the station for 10 minutes, then right to the charger.
The end result was that my Lipos balance charged to full cap in 30 minutes. They charged up faster and better with out a doubt. And held there charge better in travel to the airfield. So from now on I will be pre shocking my Lipos before they hit the charger when coming out of storage. Will give a long haul report down the road to see if batt life span is compromised. 

Happy Flying from the Pacific NW, trying to spend more time flying than waiting.  :cool:

[STOOPIDMONKEY]

RE: Batt discharge test station, Shock your Lipo.

Would be interesting to see the outcome of this. Thanks for the tip FB!

[Pleiades]

RE: Batt discharge test station, Shock your Lipo.

Extremely interesting. I thought i was crazy when mine took forever to charge the other day. Thank you

[FLY BOY]

RE: Batt discharge test station, Shock your Lipo.

UPDATE: So Far So Good. I've been pre shocking my lipos before charging and defenitly been cutting my charge times. So far batt performance has been normal and nothing lost. Its also been nice when I come home from the field with fully charged batts and just taking a few minutes instead of HRS to discharge them for storage. I was recently asked, Why not just discharge your batts on the ground and in your plane? COOLING was the issue was my reply. In the plane, every thing is enclosed and requires airflow to keep things cool. Yes the prop creates some air flow through the plane and a guy could enhance the air flow with an electric fan. But on the bench,  everything is open and the prop itself has been more than enough to keep things cool. I've been discharging batts back to back and the motor only gets luke warm at best.  Another bonus is while the batt is discharging, I can do other stuff like sit and smoke a cig, glue a part, check out other planes while the batt are discharging. Just crank up to about 1/2 throttle or so and walk away for a few minutes. Everything is nailed to the bench and not going anywhere. I love experiments! This is fun!!!!  :D

[WintrSol]

RE: Batt discharge test station, Shock your Lipo.

PRE SHOCK YOUR LIPO:

One thing that I have noticed about Lipo batts, They always seem to charge better and faster after that first flight of the day. So as an experiment, I took 3 Lipos and put them on the charger FRESH OUT OF STORAGE. They were 4s 3000mah batts.
It took a little over an hr to Balance charge each one. If you have one charger, thats 3+ Hrs sitting around and waiting.

Then I took the same 3 Lipos FRESH OUT OF STORAGE, hooked them up to my batt drain and test station.
Ran each batts at full throttle on the station for 2 minutes, then right to the charger.
The end result was that my Lipos balance charged to full cap in 30 minutes. They charged up faster and better with out a doubt. And held there charge better in travel to the airfield. So from now on I will be pre shocking my Lipos before they hit the charger when coming out of storage. Will give a long haul report down the road to see if batt life span is compromised. 

Happy Flying from the Pacific NW, trying to spend more time flying than waiting.  :cool:

Are you saying the balance phase went more quickly? The constant current portion of the charge cycle should be identical, unless the actual state of charge was higher for the post-discharge test. How about some numbers, like absolute cell voltages before starting the charge? Rough duration of the CC charge, before balancing begins?

[FLY BOY]

RE: Batt discharge test station, Shock your Lipo.

WOW, talk about over thinking it. I like to keep things simple, and understandable for even the least of these.
Storage charge is 3.80 volts per cell, as recommended to me, and is preset on all my chargers by the factory. So my batts are always at this rating while in storage. What I'm saying is when I warm them a little with a quick 2 minute discharge on the test station, They charge and balance better and faster than just putting them on the balance charger cold. It has been cutting my charge balance times nearly in half is all I'm saying. I love to fly and I really dislike WAITING for my batts to balance charge. So I'm just sharing my results. I get that test results may vary do to batt age and kind of charger. I always charge at 1C as recommended for longest batt life. Hope this helps answer you questions. 

[WintrSol]

RE: Batt discharge test station, Shock your Lipo.

WOW, talk about over thinking it. I like to keep things simple, and understandable for even the least of these.
Storage charge is 3.80 volts per cell, as recommended to me, and is preset on all my chargers by the factory. So my batts are always at this rating while in storage. What I'm saying is when I warm them a little with a quick 2 minute discharge on the test station, They charge and balance better and faster than just putting them on the balance charger cold. It has been cutting my charge balance times nearly in half is all I'm saying. I love to fly and I really dislike WAITING for my batts to balance charge. So I'm just sharing my results. I get that test results may vary do to batt age and kind of charger. I always charge at 1C as recommended for longest batt life. Hope this helps answer you questions. 

Ok, you didn't charge any faster because the battery was warm, unless you increased the charge current; the charge current determines how quickly a battery absorbs a given amount of mah. The battery being warm caused its voltage to be higher, so the charger shut down earlier. A cool battery takes longer to charge because its voltage is lower at any given state of charge. That also means you will get shorter flights if you charge a warm battery, vs. a cool battery.

[FLY BOY]

RE: Batt discharge test station, Shock your Lipo.

LMBO your funny,

What you say is true when it comes to physics, But I'm draining the volts and warming the internals by doing so. I believe what your talking about is ambient temp volts. All I know is my charge times are cut nearly in half, each cell balances out at 4.20, and my flight times are the same as always. When I check the batts after flight the volts and mah are good. I'm no rocket scientist by no means. I'm just experimenting trying to spend more time flying vs waiting. 
This is working for me, and if this goes against what you believe, I'm sorry, but the proof is in the pudding. Happy Flying from the Pacific NW.  ;)

[rc4ever]

RE: Batt discharge test station, Shock your Lipo.

When i come home with full charged Lipos i just hook them to my Icharger 4010 dual, and put it to storage charge, 5000mah 6s fully charged take about 15 minutes to discharge and get to storage charged state!! i dont understand why it should take more than 20 minutes with a good charger to discharge a big lipo??

[WintrSol]

RE: Batt discharge test station, Shock your Lipo.

When i come home with full charged Lipos i just hook them to my Icharger 4010 dual, and put it to storage charge, 5000mah 6s fully charged take about 15 minutes to discharge and get to storage charged state!! i dont understand why it should take more than 20 minutes with a good charger to discharge a big lipo??

Many common chargers are limited in discharge, to 10W or 20W. That's less than 1/2A for a 10W discharge, or about 7 hours. You must be able to discharge at over 275W to discharge that battery.

[FLY BOY]

RE: Batt discharge test station, Shock your Lipo.

When i come home with full charged Lipos i just hook them to my Icharger 4010 dual, and put it to storage charge, 5000mah 6s fully charged take about 15 minutes to discharge and get to storage charged state!! i dont understand why it should take more than 20 minutes with a good charger to discharge a big lipo??

Many common chargers are limited in discharge, to 10W or 20W. That's less than 1/2A for a 10W discharge, or about 7 hours. You must be able to discharge at over 275W to discharge that battery.

Wow, thats a way better charger than anything I got. I'm going to check in to this. It takes my chargers just as long to bal charge, as it does to storage charge. I like your charger rc4ever. Where do I get one of those?

[STOOPIDMONKEY]

RE: Batt discharge test station, Shock your Lipo.

WOW!!! $350.00 for a charger!!!! I will pass on that one. My imax B6AC+ works just fine.

http://www.progressiverc.com/icharger-4010duo.html

[FLY BOY]

RE: Batt discharge test station, Shock your Lipo.

WOW! Thats a nice charger. I really like the options, and specs. Nice, very nice. I guess I'm doing it the poor mans way. I have 5 less expensive chargers with all the bells and whistles for max safety. So I can charge 5 at a time. ALL together I'm only into it $200. including the batt discharge station, and batt bay charging station. I had really no idea that they made these kind of charge, discharge units. I just kept scrolling when I would see prices for more than $100 bucks. I'm not rich by any means. So I would save up a little, spend a little. So on fly days, I pick 2 of my favorite flyers, and charge 10 batts during pre flight checks and breakfast. Then off to the field I would go. All my chargers are A/C D/C, and my travel charger is duel port. The biggest batts I have are all 4 cell. if I could afford bigger batts and bigger planes, I most likely would have invested in better charging units.  I built the discharge station because my discharge rate on my units are only 1.0 amps, and takes hrs to discharge a batt. If I would of payed attention, Things may have turned out differently even though 4s is my ticket. Thanks for sharing, thats EXCELLENT info.  :cool:

[FLY BOY]

RE: Batt discharge test station, Shock your Lipo.

Flight Time Test  :idea:

Wintersol got me thinking, He is right about what SHOULD take place to Lipos do to batt temps and conditions while charging. So this prompted another experiment. Normally I set my timer on my TX for 6 minutes when I fly, Then land and check batt volts. At this duration, all seems fine and normal, and didnt matter how I charged my Lipos. My flight times where the same and batt volts were always 3.7 - 3.8 per cell. 

The Test: I took cool batts from storage, charged them at 1c. Charge time took in the area of 1hr and 20 mins on avg. The batts were 4s, 3000mah admirals. Put them on the discharge station and ran the batts down at 1/2 thottle while monitering the discharge with batt checker. It took 8 minutes to discharge to 3.8 volts. 12 minutes to discharge to 3.4 volts per cell. This cold test established a time base line. ;) 

Recharged the same batts after they cooled, and rechecked flight times. The results were staggering. Yes the charge time was reduced, on avg it only took 35 -45 minutes to charge my lipos. So far so good, Then timed the discharge on the station as before. The batts after 8 minutes tested between 3.65 - 3.72 volts per cell and I had to cut the test short because I achieved 3.4 volts per cell at 9 -10 minutes. The first 6 minutes were unaffected and didnt matter how I charged them. So my conclusion, A cool batt receives a deeper charge and holds more mah and does extend flight time, which would also in my mind produce longer batt life in the long term. So I think it would be safe to say, Make sure your batts are nice and cool after your first flight before you recharge, No Harm in cutting your charge times by warming your lipo a little out of storage, SETTING YOUR TIMER IS KEY!  Happy flying from the Pacific NW :cool:  

[WintrSol]

RE: Batt discharge test station, Shock your Lipo.

The batts after 8 minutes tested between 6.5 - 7.2 volts per cell 

Umm ... typo?

[FLY BOY]

RE: Batt discharge test station, Shock your Lipo.

The batts after 8 minutes tested between 6.5 - 7.2 volts per cell 

Umm ... typo?

Wow, thank you ser, all fixed now   and thank you for your input. You were spot on.

[kcsc270]

RE: Batt discharge test station, Shock your Lipo.

Great idea! My discharge function on my chargers take forever. This is a great cheaper alternative. Thanks!

[FLY BOY]

RE: Batt discharge test station, Shock your Lipo.

Greetings from the Pacific NW  :D

Update, The Long Haul: Have been pre shocking a pair of lipos before every charge all summer long. All the rest of my lipos have been treated normally. All the batts are the same age. Test results are that cold lipos fresh out of storage take longer to charge but also receive a deeper charge than a pre shocked lipo. As for batt life? UNAFFECTED AT THIS TIME. All batts are working normally with out any noticeable loss of batt life. All appears normal in the way they charge, discharge, and perform in the planes. Until the results change, I am continuing preshocking my lipos to cut my charge times in half. Thanks for reading and Happy Landings from the Pacific NW  :cool: