Cheap Lipos ?

[kevin b]

I know I'm not the first (or only one) to notice this, but inexpensive lipos appear to be getting harder, and harder to find.

Type "Lipo" into ebay and you will see what I mean. 12 months ago there were dozens of (Chinese) sellers. Now you have difficulty finding one !

Trying the usual suspect (Ali Express and BangGood, etc) gives interesting results. By the time you add on the delivery costs and VAT (now compulsory), there is very little advantage from buying outside the U.K.

I have also noticed that current costs are almost twice what they were 2 years ago. Now that is what I call inflation !!!

Fortunately I have a good stock of old ic engines, just in case and at the moment it is still possible (difficult, but possible) to brew your own fuel.

Curiously, to go off-topic slightly, I am looking at the electric car situation. The manufacturers are suggesting their vehicles batteries will last for 10 tears with constant use without needing battery replacement. I was under the impression that the batteries were based on current technology, as used by industry (and ourselves).

Anybody got any 10 year old lipos they have charged every day, that are still usable to capacity ?

I won't be buying an electric car for the foreseeable future.

[Don Fry]

12 months ago, COVID 19 was still getting into its stride. It disrupted trade, and shipping costs.

And the VAT thing,, the Uk government decided, pay your taxes. And why not, want to be a club member, pay the membership fees. 

[PeterF]

1 hour ago, kevin b said:

Curiously, to go off-topic slightly, I am looking at the electric car situation. The manufacturers are suggesting their vehicles batteries will last for 10 tears with constant use without needing battery replacement. I was under the impression that the batteries were based on current technology, as used by industry (and ourselves).

Anybody got any 10 year old lipos they have charged every day, that are still usable to capacity ?

I won't be buying an electric car for the foreseeable future.

Just think about how the lipos are used, we fliers totally abuse them, we charge them quickly in less than 1 hour to 100% full then we discharge them to 20% in 4 to 15 minutes. This really hammers them and gives them a short life. Power tools, phones, cars discharge over a much longer period which means more cycles and longer lives. If possible they charge more slowly which again increases number of cycles and life. I also believe that Tesla only charge to 80% not 100% which also increases the number of cycles and life.

Edited June 2, 2021 by PeterF

[Lima Hotel Foxtrot]

6 minutes ago, PeterF said:

Just think about how the lipos are used, we fliers totally abuse them, we charge them quickly in less than 1 hour to 100% full then we discharge them to 20% in 4 to 15 minutes. This really hammers them and gives them a short life. Power tools, phones, cars discharge over a much longer period which means more cycles and longer lives. If possible they charge more slowly which again increases number of cycles and life. I also believe that Tesla only charge their to 80% not 100% which also increases the number of cycles and life.

Exactly, the batteries are used in totally different regimes so the comparison is fundamentally flawed.

 

Also they use lithium-ion cells, so again, very different in cycle characteristics.

 

I would happily have an electric car right now: my commute both ways is 15 miles and with an average of a 200 mile range under median conditions I could feed the car for a couple of quid every two weeks(ish) as opposed to £60 for a full tank of diesel every 6 weeks(ish).

Edited June 2, 2021 by Lima Hotel Foxtrot

[kevin b]

I don't disagree with the argument LHF (not that it is). However people who work in industry (I was one) will soon tell you about the life expectancy of power tool batteries. I use my (old) phone (no internet) and a battery can last me up to 6 years (maximum). Ask a typical iPad user how long their batteries last (if they keep them long enough, before buying a new one).

With regards to Electric cars, do you think they will come down in price (for a new one) the same as electric aeroplanes did ?

Also, don't forget that the government derives a large amount of its income from taxes on motor vehicles. Do you think they will let you get away with paying a "couple of quid" every two weeks once we are all running electric cars ? All these new vehicles are capable of (and most do) telemetry (just like our aeroplanes).

Big brother may not be out there yet, but all the systems are being put into place.

I am not a conspiracy theorist. Just a curious observer with a bit of a cynical attitude built up over many years of observing human nature.

  

[Trevor Crook]

I recently bought some 4000mAh 4s lipos from Hobbyking's UK warehouse for £24 each, which is cheap enough. They are only rated at 20C but I measured their cell impededence and it's lower than some 30-40C ones I have. They have plenty of punch in practice too.

Comparison of EV batteries with the types we use, or indeed phones etc, is fairly invalid, for the following reasons:

1. They use different chemistries, optimised for performance, cost and longevity. EV manufacturers typically give an 8 year battery warranty.

2. They are used far more gently than our cells. A modern EV will typically travel for 200 miles on a charge, which at an average of 50mph equates to an average drain of 0.25C. Home charging is typically around 0.1C, although public rapid chargers will give 1C, and sometimes more.

3. The car's battery management system (BMS) is very sophisticated. It will moderate the charge rate depending on charge state, temperature etc. It will also prevent you driving until it's flat, of course. For instance, the VW ID3's 58kWh battery has an actual capacity of 62kWh, but the BMS prevents it from going down to 0% or up to 100% to prolong its life.

Hope this dispels some of the myths.

[Nigel R]

All more than adequately answered above.

 

I can only add that manufacturing is highly likely to be more tightly quality controlled for EV batteries, us hobby users do not pay for much in the way of QC.

 

Car battery suppliers do not want to have to deal with warrantee jobs such as replacing a single cell from a large pack at their own expense.

 

Conversely, with our small lipos, if you wind up with a pack that shows a dicky cell after a few cycles, unless it is truly DOA, then that's largely our problem to deal with.

 

As for not buying an electric car? That choice may be somewhat mandated by what is available. Nothing solely IC to be sold after 2030.

Edited June 3, 2021 by Nigel R

[PeterF]

Interesting article from BBC a few days ago, electric car sales are now growing exponentially and was around 5% of total car sales last year. Give it a decade or less and most car sales will be electric.

 

Why electric cars will take over sooner than you think

[Mitchell Howard]

4 hours ago, PeterF said:

Interesting article from BBC a few days ago, electric car sales are now growing exponentially and was around 5% of total car sales last year. Give it a decade or less and most car sales will be electric.

 

Why electric cars will take over sooner than you think

 

FYI, that's just a link to bbc.co.uk.

Edited June 3, 2021 by Mitchell Howard

[Trevor Crook]

I have found that I have the odd pack fail within 20 charges, but beyond that they go on for a hundred or more. My packs are all budget brands, mostly from Hobbyking.

My first lipos some years ago were also budget ones, from a company called RCMDirect. Despite being at the bottom end of the market, a 2200 3s 10C pack was about £30, which puts today's prices in perspective. 

[PeterF]

Here is the link again, I have a new tablet and it appears it only copies the root part of the URL for some odd reason.

 

https://www.bbc.co.uk/news/business-57253947

[SIMON CRAGG]

 All my recent packs have come from China Hobby Line. Free postage over $85.00, excellent reviews (mainly from the US), and they have some outstanding promotions.

 

Would not purchase anywhere else.

[J D 8]

               JCB the digger maker is developing Hydrogen version of Internal combustion engine. You never know we might model version one day to keep us IC flyers happy.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

[Piers Bowlan]

On 02/06/2021 at 20:32, kevin b said:

Anybody got any 10 year old lipos they have charged every day, that are still usable to capacity ?

I won't be buying an electric car for the foreseeable future.

Until recently I thought that it would be another three years of so before EVs 'became of age' and I would want to buy one. Then I did my own research and started to look seriously at the Nissan Leaf in particular. To cut a long story short I bought one last week!

 

At 5p kWh it costs about £3 for a range of 200miles on it's 62kWh battery although the claimed range is about 230miles. Potentially, it could save me around £2000 a year on diesel, on the basis of 12,000 miles a year, although in reality I will still use my big diesel for towing (caravan/boat). Insurance is really cheap as is the annual service. No road tax either. But who wants to drive a milk float? I hear the naysayers carping. Well, 213hp and 0 to 60mph in seven seconds with the acceleration linear and silent. Awesome! The battery is guaranteed for eight years and yes, it will degrade, but even if it loses 25% over the next eight years it will still have a range of 150miles, which for me is OK when you consider the 2011 Leaf only had a range of 60miles on its 24kWh battery. Yes the performance will also degrade too but then if you buy a new ICE car it will not drive like new after 100,000 miles either. Expensive? A top of the range Leaf has an OTR price similar to a Ford Focus Titanium, Auto, diesel as it benefits from the government £2500 contribution. Resale value? A six or seven year old Leaf will still have a forecourt price of about £7000, which stands up well to comparison. I should be on commission! 

 

EV cars will become mainstream sooner than you might think and the global demand for lithium will make our LiPos ever more expensive, so stock up now!

 

 

[Ian Whittaker]

On 02/06/2021 at 21:54, PeterF said:

Just think about how the lipos are used, we fliers totally abuse them, we charge them quickly in less than 1 hour to 100% full then we discharge them to 20% in 4 to 15 minutes. This really hammers them and gives them a short life. Power tools, phones, cars discharge over a much longer period which means more cycles and longer lives. If possible they charge more slowly which again increases number of cycles and life. I also believe that Tesla only charge to 80% not 100% which also increases the number of cycles and life.

Tesla give you the option of either 80% - for normal use and with a nod towards battery longevity- and 100%, to give max range on a longer run.