Hiya. My charger is a version 2 type not version III and therefore doesn't have the HV setting and I do check it is on Lipo. Next time I charge the battery I will take note of everyone's input. Thanks D

As Dave said, check with another volt meter, (preferably a multi meter) If you can find one, The GT Power watt meter is the best tool you can have. It checks Amps, balances (shows individual cells while balancing or using as a volt meter in line etc. Hard to find but by far the most useful tool for batteries. Does LiPos , LiFe, and LiLo. Also does temp. You have to solder your own plugs on. This place may still have them, buy one while you can if they do

https://www.robotbirds.co.uk/g-t-power-100a-multifunction-watt-meter-lipo-capacity-and-cell-checker.html

GT power still list them on their home site, but for some reason they are hard to find. They will do everything you need for battery checking. Some shops in UK still seem to advertise them.

A good charger is latest Sky RC IMax B6 Evo,

https://www.aliexpress.com/item/1005003731167659.html?spm=a2g0o.order_list.0.0.21ef1802MLo3Lu

I've just bought one and they seem very good. Sky RC have been making chargers for years, - first charger I bought was a Sky RC ICharger and it's still working perfectly after 13yrs. The new one can have all your batteries and settings programmed in, (up to 10 batteries) so you don't have to re-set every time. Once you have them set, you just pick the battery and press start. Little bit tricky to get the hang of setting, but once you get the idea it's easy. Has alarms if you do something wrong, and stops itself (forget to put balance lead in, wrong cell count input etc) Quite idiot proof.
As Dave said, check you are not charging on the HV setting, - might be why you are getting a strange voltage. GT Power stuff is usually pretty good.


If you have a multi meter, you can test individual cell voltages by checking on the balance plug ie neg lead on meter to neg on plug, then test along the pos contacts (should give you voltages increasing by same amount) eg 3s charged would be - 4.2-8.4-12.6

http://www.gt-rc.com/en/pd.jsp?id=393#_pp=126_765

Your charger should be ok, but it's good to be able to see the individual cells as it helps spot possible problems.

JB

Thank you. All your advice much appreciated. Cheers Duncan

Thanks for all your advice but I'm still wondering why when the charger says 100% full it is 14.1 volts and not 12.6volts. I only charge at 1.5 amps for probably about 50 mins. There doesn't seem to be a lot of capacity between 12.6 and 11.1v. I have attached photos of the device I use to check the voltages and also the discharge light assembly I have made. Perhaps in future have to charge to about 80% capacity. What do you think please?

Just an additional comment re your charger. It has a setting for Hv LiPos which will charge that Hv type of battery to 4.35v. In your case you need to select the LiPo option for 4.2 v max. Also make sure 3 cells are selected. What instrument gave you a voltage of 14.1volts? If it was ther charger it could be faulty. A check with another voltmeter should confirm this. If it is faulty the max charging current might be faulty also. If you need to change I use a Giant Power Intelligent Balance Charger G6AC.
dave976

Sorry to have confused. I was referring to the min discharge voltage. Modern higher capacity batteries now recommend a min discharge of 3.5v per cell. Earlier lower capacity batteries recommended 3v per cell. I use 3.5v as my cut off voltage to preserve the life of my batteries. Suitable ESC's have this as a default setting but are also adjustable to other cut-off voltages. The ESC doesn't cut off completely it just limits the current draw to a sfe low level to allow you to return the model to shore.
Dave976

That charger is quite suitable for your purpose providing you use the main connector and the smaller white balace charge lead.
dave 976

Sorry meant to send this one!

Thank you for all your very useful information. I've attached photos of my charger. I've just checked the voltages whilst in storage and they are 3.7, 3.7 and 3.6. I've also double checked my bulb that I use for discharging. I think it is probably indicator an bulb as it is a 12volt 16w bulb. What charger do you recommend it you think mine is unsuitable. When I was looking for a charger I was informed that a well known trusted charger had been copied and wasn't safe so I stayed away from that make - just in case I got an imitation one.

Thanks, JB.
Great information👍👍👍
I also bought a LiPo bag to charge them in🔥🔥
Trev

14.1 V is over charged,! should only be 12.6 V max for a 3s. (4.2v per cell,- 11.1v is the starting/(initial new voltage before charging,)- LiPos normally work between 3,7v and 4.2V per cell ) Storage charge should be about 3.8V per cell. Don't let the battery go below 3.5v per cell if poss, (3.3 absolute minimum, and even that is really too low, - down to 3v will probably kill the battery pretty quickly and it won't be able to be charged fully. If your charger is over charging you (or the charger) are doing something wrong, and it could end up with a fire. Could also be a faulty battery.

Make sure you set the charger to balance charge, Connect the balance lead correctly, make sure the cell numbers and capacity settings are correct, and set a time limit (about 60 mins at 1.5A charge rate for a start from storage voltage, and watch the individual cell voltages carefully while it's charging (if your charger has that capability.) If it looks to be going over 4.2v, STOP THE CHARGER, and if you have set everything correctly, and the charger is not doing what it should, buy a better charger and bin the old one, or try a different brand of battery and see if the same thing happens (for your own and others safety) . What charger are you using ?

You can use a tail light bulb - tail or stop filament,- halogen headlight is a bit fierce (about 4.6A) with a voltage monitor set to 3.8v (alarm setting) on the balance lead, but stay nearby so you can monitor it as well. Once it's down to that voltage put it on the charger set to the storage setting as Mike said. (all the correct settings apply here as well.) Doing it with the charger is a better option until you are fully conversant with LiPos.

JB

No it’s best to use the selection of charge/discharge/storage/ plus others that are available on a propriety model battery charger I wonder what type of charger you are using.

I have an overlander 2230mAh battery which shows on the casing 11.1v 3s (24.4Wh). It also shows 35c constant discharge/65c bursts. When I charge it fully, it shows a voltage of around 14.1 volts. I was confused when you said it can be damaged if '3v or greater' in which case for a 3 cell it should only be charged to 9volt. Therefore I think I have miss understood your text. After sailing I always discharge it to around 11. 1 volt by connecting it to a car headlamp bulb. Is this the correct way to use this battery please? Thanks in advance as I'm relatively new to lipo batteries.

Hi
You can get a battery alarm which plugs into the balance charge lead and also the better ones read your total voltage and each cell voltage.
Banggood and Hobbyking have them.

Canabus

If I could just add to the very good advice already given. LiPos will be damaged if discharged below 3v or higher, this damage is cumulative and involves an irreversible chemical change in the battery. You can buy add on devices that sound a warning when the voltage of a cell drops below the set min voltage but many ESC's now come with built in protection which does a much better job. Water is best kept out of our models whatever battery system we use. I always place all my electrics as high inside the hull as possible as water will always find a way in.
dave976

Thanks, JB
Trev

Hi Trev, as long as you get a quality charger, follow all the safety advice, (heaps on YT) balance charge them, (cells should be within a few points of each other - pref no more than .3v) storage charge/discharge when finished, NEVER poke holes in them (ie keep all sharp objects away from them at all times,- especially modelling knives), don't drop them (they can puncture on sharp stones etc) generally treat them well, they will last for years, (my seaplane tender in the last vid was using 2x 2s 2200mAh 25c LiPos from 2011) LiPos have more constant power than comparable batteries and far less weight/Watt .

Any old or dud cell batteries can be safely discharged in a bucket of salt water for a few days (or till the bubbles stop) for safe disposal (I bang a 6"nail through them after that to make sure they are dead) - a good number of rubbish trucks have burnt out from live LiPos being crushed in the compaction cycle.

All batteries with high amp outputs are dangerous (try shorting a fully charged 12v NiCad and see what happens)😮 they can burn your house down too, (I'd guess more cars have caught fire in garages round the world, or heaters, or cigarettes burning houses then LiPos) A lot of uninformed scaremongering about LiPos has put people off them, but as long as they are available, I'll use them every time, especially in planes, (try getting a plane with 2kgs of NmH batteries off the ground as opposed to a 400g LiPo for the same power😁)

Hope this helps PS- if they get wet, just let them dry, (just not in the sun)- probably means if they start leaking,- but you'd soon know if that happened😁 If they fell into salt water, it would just start discharging them.

JB

Thanks, Rowen👍
Trev

Have now used LiPos for some years quite successfully.
Recommend follow the guidance and should be fine.
I use a 3s in my RTTL and it works fine - there is a blog on the site.
The cells are sealed so cannot think how a relatively short submersion will damage them. However, they do contain an incredible amount of energy that could short out and do damage.
I always remove both before and after use and wipe down if damp.

Thanks, Duncan.
Sound like you are doing it right.
When storing them you are supposed to store at half charge, according to the directions.
Trev

I'm fairly new to all this newish tech but I'm using a 11.2v lipo in my RAF crash tender - no problems so far. They apparently can be a bit unstable so having charged it to 14 volt I always discharge it to 11.2v by connecting to a car battery headlamp before putting it away. I also store it in a fireproof bag in inside a metal cash box when not in use. It might be an overkill but I'd rather be safe than sorry. My wife would never forgive me if it set on fire! I believe the newer lipos are a lot more stable. I believe that not all ESCs are compatible with Lipos. They are a lot lighter and more compact than Nihm. Someone please correct me if I'm wrong. Good luck.