Morning Peter.
Interesting re your batteries after such a length of time,but glad that they seem in reasonable fettle.
Here’s hoping they hold up ok.
Re your battery alarm,what type do you use as I have not tried one previously.
Regards Bill

Peter,
Reading! whatever next 'Instructions'LOL!!

Martin555.

Thanks for the article. Most of the content is regarding what the users should know before using them, but I found the section on how they actually work written in plain English very interesting.👍

For a really informative article on LiPo batteries that explains the technology and the correct use I recommend you look at
https://3dinsider.com/lipo-lifespan/
The technology is still relatively new to many hobbyists but is sufficiently different to our earlier types of SLA and NiMhs etc to warrant some helpful guidelines to explain the safest way to use LiPos.

Thanks JB. Very useful information. I have battery alarms which I do use every time. I will check to see at which voltage they trigger.
Thanks.
Peter.

Hi Peter, As long as they were stored at a storage charge, they should still be in reasonable condition. I have batteries from 2011 which are still perfectly useable in my boats. Probably will depend on your Amp draw at full power, but at moderate throttle they should be ok.

A way of telling is, if the battery is fully charged, and you give the boat full power and you hear it 'flatten off' before full throttle, you will know they are getting down a bit. Doesn't mean you can't still use them, as long as they balance near enough after balance charging, (I also manually balance with a separate balancer as well after charging), just means you will just have to drive slower.

If you use a battery alarm (I set mine for 3.8v/cell), it will tell you if you are over drawing the available discharge capability of the battery (or a particular slightly weak cell). If the alarm goes off, just reduce the throttle till it stops, and you will probably find you can carry on for quite a while still. Just make sure they don't go below 3.5v/cell and they should last for years, but slowly reducing in available run time.

JB

It is now two years later. Due to circumstances beyond my control, I have been unable to do anything with my batteries. I now live in Hungary and so should have more time for running my models.
I have checked the charge levels and they are still very reasonable. The lowest cell voltage I found was 3.72 volts. I have charged a few to use and they charged really well. I will be using them in a model in the next few days so I will be able to report on whether their life has been affected.😀

Peter.

It is almost 9 months since I charged the new LiPo batteries for storage. Unfortunately I still have not used the 4s 4500 batteries since then but I do check them every 4 months to see how they are. They have been good so I have not had to do anything with them. I decided on this visit to replenish the storage charge on all of the batteries. I was shocked to find out that all of the batteries were almost perfect with only a few minutes of charging required, but the two 4s batteries, the oldest, did not take a charge at all. They are still very good. I will use them when I return here in August.

Hi Pete, welcome er Home?😉
I'm not too surprised at your results with the new LiPos.
That's exactly why it is recommended to put new LiPos through about min 6 max 10 charge / discharge cycles to 'condition' them, i.e. get 'em used to their working life😉

I'm not surprised at the short run times either. I seem to recall you have two hefty motors in your boat! Let's say (for simplicity) the motors draw 1.8A each. Therefore one motor would (theoretically!) run max 1 hour on a fully charged 1800mAh (1.8Ah) battery. Two such motors only half an hour etc etc.
If (more realistically) they draw 10A together (probably more!) then they can theoretically run at that current for 0.18h or 10.8 minutes on a fully charged battery. QED.
Theoretically cos you don't want to empty the battery and run it into 'Deep Discharge', i.e. less than MINIMUM 2.7V per cell. They don't like that and get stroppy; don't charge properly or worse 😲
You get the drift! 😉

If there's a danger of the river freezing over - you've got 4 months to build an Ice Breaker😁😁So get cracking😉
Cheers, Doug 😎

Hi Doug and all.
Delay in answering your post as for some reason, my phone was useless on the internet.
I did not see your post about checking the capacity percentage until I returned home, so that is why in April my checks were not complete.
On my return to Hungary a couple of weeks ago, I checked the batteries and they were both at 3.85 volts per cell and at 51% capacity. When they were new, they were at 31% capacity.
My new smaller batteries were also at 30% capacity and when I left on a storage charge, they are also at around 50%.
The new, lighter 4S batteries are 1800mAh. On the first full charge they only gave me 89% capacity. I used them both, unfortunately they lasted about 6 minutes each, and recharged. This time they charged to 99% and lasted 10 minutes. Hopefully they get a little better after a few uses.
I am now back in England and when I left, all of the batteries were at around 3.86 volts per cell an 50% capacity. I will check again at Christmas but I will have to see if the Danube freezes to see if I can use the boats then or not.😉

That's the one! Even recognise the writing. Very Germanic. I can only find it on a Polish site, so it figures I should go to one of the several Polish shops in out local town (Wisbech) which is very much Eastern Europe in Fenland these days. Many thanks. Let's hope I can get some.
It seems mad that I paid 3-50DM for it in Sauerlach back then which was about £1-50, a derisory sum. Now it's about 7 quid if my Polish-Pound sums are right, but it's still well worth it. I hate dry wines, like most French. I see no point in paying through the nose for what I wouldn't even put on my chips!
My favourite day to day wine is a Spatleser, although Chateau de Lardilay from Cadillac is rather nice. Sorry if the spellings are awry.

Thanks for the link!

Martin

Thanks John
I hope Martin picks up on this. The Spätburgunders are something for him not me!
They are 'Lieblich' wines, too sweet for me, cos the grapes are picked as late (spät) as possible and have a higher sugar content. Not all of which is converted to alcohol.
BTW: i tried a few links with the result 'Not available at the moment'.
Guess the spät crop is a bit limited🤔
Cheers (!) Doug 😎

See this lot Doug.----https://www.google.co.uk/search?q=Erben+Merlot+Spattenburger&oq=Erben+Merlot+Spattenburger&aqs=chrome..69i57.34947j1j1&sourceid=chrome&ie=UTF-8
Enjoy Salut John😋👍

Hi Martin,
Yeah, you mentioned this about a year ago but as yet I haven't seen any of their wines. I don't get quite as far south for shopping as Sauerlach.
The furthest I go south is the relatively new conglomerate of mega stores just outside Unterhaching. Then usually just for the garden centre and electronics store. But I have noticed that there is an 'Up Market' supermarket there. I'll keep me eyes peeled for you.
Can you give me a net link for Erben?
On reflection I think that one of the finest wines I have ever drunk was the Chablis at dinner in Cherbourg while visiting the CMN shipyard there. Superb fish as well 😋
A good Muscadet comes a close second though😋😋
Prost, Doug 😎

Which reminds me, Doug. Any sightings of what to me is the finest wine I ever drank (excepting Chateau d'Ychem..... Erben Merlot Spatbergunder. I bought it for a laughably low price in a little general stores in Sauerlach, a kind of quadrant of shops with a bit of parking available.
I have found mention of it on the 'net, but not a supplier. So, if you do happen to see a bottle, would you get me at least three and I'll pay you immediately for the wine and the postage!

Cheers,
Martin

A chaque un a son goût John 😉

I'm not tooo surprised at your NiMh results. But I also think that you are correct that they won't last the proverbial 5 minutes on load.
I had a similar experience last year when I retired and took stock of everything lying around in boxes and shelves in the so called workshop😲 Some also measured above the 'dead' voltage but collapsed within seconds of applying a load; a 540 motor running offload. They were consigned to the Great Recycling Centre in the sky 🤔 The NiCads had preceded them by a decade or so!
Since then I've restocked with LiPos where I have brushless and LiPo safe ESCs and NiMh for the 'brushed ships with older pre Lixx EScs.
For heavier jobs like Graf Spee (3 x 600), HMS Belfast (4! x 385), U25 (2 x 385) I've restocked with 6V 4Ah SLAs.
Have started compiling an XL spreadsheet to keep track of them; when last used / charged etc.

Oooops! Just discovered that Grauer Burgunder is an excellent cleaner for my inductive mouse pad 😲
Prost allseits! Doug 😎

I don't intend using Lipos when I get back to actually boating and flying as I feel they are too much bother. Lion orABC or similar for me I think.I'll have to think more on it. I have Nimhs and A FEW Nicads .The Nimhs I know for certain are 13 yrs old at least and are showing 11.2v at 82% charge despite not being charged for 4 yrs. The Nicads 9.4v and 42% charge. Not as good; as we might expect but the others really surprised me when I metered them out.8 yrs lying in a blokes planes,boats and boxes and I got them 5 yrs ago.I charged them all and they've not been charged since.We'll have to see what happens under load etc. They might not last 5mins.🤔 John O/T👍
I know some of you won't believe me so tuff. J😎

Hi Pete,
Do you have a Battery Capacity Checker? Like in the pics?
Open circuit voltage is NOT a reliable indication of the battery's charge state😲 As you can see in the pics my two bats, 1 LiPo one NiMh, both show voltages above the nominal value. But the capacity / charge state less than half!! Be warned! Believe I did suggest to you to note the capacities before you left Hungary last time.
Whatever - Have Fun😉 Cheers, Doug

Hello all.
I have now returned to Hungary after 4 months. I left the batteries at a storage charge of 3.85v per cell. The reading now on both batteries is 3.85v on 3 cells and 3.86v on one. Strangely both batteries are exactly the same.
Conclusion is that relatively new batteries hold their charge very well even if not used for months. I will keep checking them every visit.
Unfortunately these batteries might not be used for a couple of years as I found that 2 4s 4500mAH units (using only one at a time with the other supplying balance in the water) were a bit too heavy for the boat and made it low in the water at the stern. I have replaced them with much smaller and lighter 1800mAH LiPo`s. We will see how long they last under load.🤓😉

Evenin' Peter, hope you noted the % capacity before you left, be good to compare with the value in August. One more tip; store batteries cool.
It slows down the internal chemistry which reduces the capacity. See attached tips from the fly-boys😉 Oh! And welcome home, cheers Doug 😎

Thanks Doug. I checked the percentage fill when I received them. They were 31% at 3.67 volts per cell. I am now at home so I cannot check them again until August.😱

Hi Peter, check the capacity as well as the voltage. Around 20 to 40% is normal for storage and when they are delivered new.
Cheers Doug 😎

I have now left the batteries at a storage charge of 3.85 volts per cell. I will let you know where they stand when I return in August.
The ammo boxes are a great idea. I bought two from ebay at £12 each. They are of super quality. I have transported one with the boat to my boating river in Hungary. The other is here.
Thank for all the advice. it made things a lot easier than they could have been during my first uses of LiPo batteries. They are much easier to use now that I have some experience.😊

My charger has a storage setting which i always use after a sail as insisted by our local battery supplier guru. No problems at all with durability, full charging or high amp useage. Wrap 2 elastic bands around your stored lipos so you immediately know its status. The first elastic band is put on to a used battery immediately upon removal from model.
Works for me now i am nearing 70 and my brain function 'aint what it used to be'

👍

Reduce the voltage to a holding charge for that four weeks.
Better safe than sorry & better for the longevity of your battery.

Good morning all,
Many thanks Ron for your information.
Can I ask:- say you only using your batteries every four weeks or so, should we leave them with full charge or should we reduce voltage to holding charge for that four weeks?.
I understand this could be a "how long is a piece of string" question.
Norman.

Hi all,
Lithium-Ion and Li-Po batteries do not take kindly to being stored long term fully charged. When they are new they will do it but after 2 to 3 years of intermittant use, can start to swell a bit and that is where the dangers start.
When you give these cells the final run of the season and they show a charge in the the 3.3 to 3.5 (or so) volts per cell then they can be stored relatively safely. (This is called a holding or factory charge) Re start them with a balanced charge before you next use them. Do not constantly fast charge them as thi could induce swelling of the pack earlier.

The old Ammo box is a good idea, any strong metal box will do but store them where it does not get very hot or very cold and ideally not in the house.

Lipo cells are accepted as hand luggage by most airlines and a holding charge is recommended when flying, so remember to take a small 12v DC balance charger or 'Intelligent' charger with you to other countries, you will always be sure of a power supply, like a car battery even where the mains voltage is different.

Small black plug-in cell monitors are readily available from places like Component shop and are a good guide to cell condition. One is these is quite essential as we use these cells more and more.

Cheers, hope this helps.

Ron.

Not sure it's a good idea to leave your lipos for that length of time with a full charge, I personally, put my lipo batteries into "storage" mode otherwise you may find they expand if left fully charged for long periods. I may stand corrected.
X mod rifle range warden, I to use old .762 ammo boxes to store my lipos👍

Thanks. I am glad I only have to fly with it once.😊

Good idea 👍
I have an ex RAF ammo box I've been using as a tool box for years (decades😲).
The tools will now have to find somewhere else to sleep 😉

I have found a similar situation with li po batteries. After standing for some time when I have connected them to the charger there are not as depleted as I thought.

I had an interesting find last year when I was in a second hand shop in North Wales. There was a large metal ammunition box that appeared to be of WW2" vintage and they only wanted a tenner so I bought it.

I keep my li po's in it with the higher capacity ones also in the box but in the fire resistant bag. The box of course has a lid that securely closes with two catches.

😁 Boaty

I use lipo batteries in my transmitter and last year I had to take time away from the hobby because of my health.
When I checked my transmitter the battery was still showing 10v on a 11.1v lipo this is a full year after last charge so you should be fine for 4 months as long as it's charged before it's left in storage.