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"Low Voltage" lipos. What now?

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"Low Voltage" lipos. What now?

Old 04-23-2010, 08:42 PM
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Chip_Mull
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Default "Low Voltage" lipos. What now?

I have several questions on Lipo batteries. I inadvertently left my battery on and drained it down. Now it won't charge it says "Low Voltage". Is it finished, nada, no more, throw it away? I have purchased three top 0f the line chargers all purporting to be the best and my batteries will NOT fit any of the balancing plugs. THEY ARE ALL DIFFERENT! Is this industry just not standardized or am I missing something there. Apparently I need a handful of plugs to change from one to the other(S).
Old 04-23-2010, 08:53 PM
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The pack is undoubtedly damaged. There are 4 different taps , you must have 3 different ones on the charger and the 4th one on the battery.
Old 04-23-2010, 08:55 PM
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Charge each cell individually at a very low current to 3.3V. Some come back, most don't.
Old 04-24-2010, 07:37 AM
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When the voltage drops low enough in lipo batteries, the cells change chemically.  Even if you can get some or all of the cells to take a charge, the battery will never again perform like it did.  You need to replace it and keep the replacement charged.  Never let lipos fall below 3 volts per cell.
Old 04-24-2010, 11:34 AM
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To follow up on that thought,, I'm getting back in racing and going to lipos for my cars/boat

Do many use the "low voltage Cut-Off Modules", they seam like a good investment @ $25 each

How do you guys do in in an airplane ap? same type of module?
Old 04-24-2010, 11:47 AM
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Great question! That seems would have saved me a cou0ple of batteries already. Where would one get such a thing?
Old 04-24-2010, 12:02 PM
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ORIGINAL: scale only 4 me

To follow up on that thought,, I'm getting back in racing and going to lipos for my cars/boat

Do many use the ''low voltage Cut-Off Modules'', they seam like a good investment @ $25 each

How do you guys do in in an airplane ap? same type of module?
If you mean a fail-safe which shuts of power if one inadvertently leaves a pack plugged in... no, I haven't seen those.

But aircraft ESCs have a built-in Low Voltage cut-off (LVC) so that in normal in-flight use one cannot discharge Lipos to below ~3.2v/cell.
Old 04-24-2010, 12:34 PM
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ORIGINAL: Chip_Mull

Great question! That seems would have saved me a cou0ple of batteries already. Where would one get such a thing?
These are intened for cars/trucks/boat,,,
http://www.teamnovak.com/products/li...ule/index.html

ORIGINAL: Dr Kiwi

But aircraft ESCs have a built-in Low Voltage cut-off (LVC) so that in normal in-flight use one cannot discharge Lipos to below ~3.2v/cell.
sorry,
I'm a newbie to elect airplanes, are these programable typically depending on the pack size?
These work instead of a BEC or just basically a BEC with a different set voltage point?

edit:
found my own answer, some new ESCs detect type and cell count,,, what will they think of next?








Old 04-25-2010, 01:25 PM
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Hold everything about a gadget that prevents running your battery TOO LOW if you FORGET TO TURN off ALL POWER.

NEVER seen or HEARD of such a device.

It would have to be very intelligent to know when you are REALLY finished with it.

ONLY YOU CAN PREVENT RUINED ......rechargables........You and nothing or no one else.

ALWAYS pull at least 1 of the battery leads apart......Only sure way of protecting a battery from being ruined.
Old 04-25-2010, 01:34 PM
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About all the different battery charging plugs...........It sucks.

I can solder very well. Find someone who can. Have them change ALL your battery plugs & the charger plug to be the same type.

My FMA cell Pro 4 has many different adapters available for those who can not or do not want to cut & solder.........I build my own battery packs from B & D & Dewalt power packs. Very safe to do as the cells are metal covered compared to LIPOS.
Old 04-25-2010, 02:11 PM
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My ESC had a push button on it that lit up when you turned it on. The blue light went out when you pushed it again and all functions stopped. Silly me, I thought it was a switch. The next time I tried it, the battery was dead. It was then I ran into the "Low Voltage" issue.

I only use Deans connectors on my batteries and chargers/balancers (which I solder). The balancing plugs on the chargers never seem to match up with the balancing plugs on the batteries. Are you suggesting I have to change every balancing plug in order to standardize?

I KNOW how to solder. What I don't know is how to replace a female balancing receptacle on the electronics. These things are assembled by robots and soldered with minute connections. Why can't we insist the Chinese use the same connectors on all balancing plugs? After all, someone is ordering them by the container load.
Old 04-25-2010, 04:40 PM
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I do it to every pack I build. Do a couple at a time. Everyone you complete is 1 less agravation.
I ....cut 1 WIRE at a time and immediately splice it into the new place & shrink tube the connection..........NO SHORTS that way.
I also have a 6" long seperate connector that is left plugged into the FMA charger permanantly. That takes all the plugging & unplugging wear & tear. When it gets flaky, I just buy a new 6" connector instead of butchering or having to send the charger back for a repair job.

Old 04-25-2010, 04:49 PM
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I do not know of any ESC that has a switch connected to it, that removes all current drain from the battery. Any switch always controls full power ( arming ) to the motor only.
Some DO NOT even do that, IF... IF... the transmitter is NOT turned on. Those can & do put any amount of power to the motor at any time.

CRAP & dangerous !!

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