Batteries and New Battery Technologies

Missed the mention on the "D" type of batteries used in this sub?

One of the oldest and most efficient EVs uses several hundred small cells in series for propulsion. http://www.twike.us/the_twike.html
It still has a cult following in Europe. Very impressive even with the nicads when I was given a demonstration drive in Seattle many years ago. I see they have switched to lithium cells to further increase performance. Quickly seems to sell out of each production. Appears to have a very advanced BMS.

The battery pack consisted of sets of individual hard wired modules in the old Twike setup, as I recall. That allowed easy replacement of smaller units upon failure, though not individual cells. Even the Prius and other hybrids use modules of smaller cells today, if I understand the pictures correctly.

So if I understand your project correctly, you are trying to do what has been done before but WITHOUT hard fastening (welding or soldering) of the individual cells. Whether this can be done to produce a reliable pack with 8000? individual touch contacts that are NOT hard wired seems the more appropriate question. Mechanical switches seem to use the principle successfully, but are built with very little wiggle room. So immobilizing the individual cells while under high contact pressure might be the key. It would be easier if the cells were designed with individual quick release mechanical terminals in the first place, maybe like we see on the small, boxy, 9v batteries- but say, with higher quality interlocks. Whether strong magnets or special contact paints or gels will maintain electrical contact through continued vibration seems to be another part of the question. If the magnets or other methods wear through the layers of plating upon vibrational contact, then they may not hold up well in mobile applications.

Hope this helps.

Porta

 

New White Paper by Altairnano

Altairnano has recently produced a white paper entitled Applications for Advanced Batteries in Microgrid Environments. The white paper discusses the reliability challenges of isolated, inflexible grids and the way advanced batteries can address those challenges. To access the white paper click here.

 

Renewable Energy Storage Website

This link will take you to the Renewable Energy Focus website, Energy Storage subfolder.
The whole site is massive, so I had limited time to check it out, if any of you has more time, there might be some interesting things there.
Here is the link: http://www.renewableenergyfocus.com/category/66/energy-storage-including-fuel-cells/

 

Hi Porta,

Sorry for the late reply, I went down with bronchitis.
Yes, that is indeed the correct picture, but over and above what is different, I don't believe in connecting batteries parallel, except via a means of seperation like diodes, MOSFets etc. Also I try first with rubber force instead of spring force. I believe that rubber does not corrode at sea.

Thus the BMS is much simpler in detecting problems. If one connect batteries parallel, in that case every battery has to be measured for temperature, voltage and over or undercharge.

Thanks Porta, I have ordered 40 extended (33mm x 90mm) LiFePO4 type "D" batteries to experiment with them.

They will be delivered at the end of November. (545 USA$ ) it is a little above my aim of $500, but so what.

That paint conductive glue is mighty good stuff.

Bert

 

Carbon Nano Tube Coating , modify lead acid battery

..maybe a good interium technology to carry us thru to higher techs of the future?

EcoloCap Solutions Inc. (OTCBB: ECOS), with its subsidiary Micro Bubble Technologies Inc. (MBT), today announced that it is releasing preliminary comparative testing results on the MBT CNT-Battery prior to the product’s official debut at a Company hosted event in Korea on November 18th.

The MBT CNT-Battery is a 99% recyclable, rechargeable battery that utilizes a highly-conductive carbon nano tube coating to modify the fabrication of standard lead-acid batteries. The initial CNT-Battery line is a series of 12 volt modules with varying ampere hour capacities which will be available in both standard and alternative sizes. This line is designed to optimize customization and will allow users to scale voltage and capacity for use in everything from golf carts to industrial power generation.

While official independent testing of the 12 volt series is expected to be made public in early 2010, the Company is releasing select preliminary comparative data. The following table offers a side by side look at a standard energy dense configuration lead-acid battery from a leading manufacturer compared to a similarly configured MBT CNT-Battery....

http://theotcinvestor.com/ecolocap-releases-cnt-battery-testing-results-831/

 

The ump-th Star Trek story. 1200 Ah battery, 45 minutes charging time, that means charging with over 1500 Amps. Utter nonsense!

 

Hi CDK,

You are sharp ! Nothing can fool you. I like to see the transformer or switchmode powersupply at those Ampere rates. You are so right. 12 Volt x 1200 Amphr = 14,4 Kwh, which utility will allow this from a yachtclub. None. A garage? Maybe, but certainly not from your home.

But, lets wait and see.

Bert

 

Charging like this can be done using "dump" charging like EV drag racers do when they need to set up for the next race. Not easy or ideal, but can be done.

Porta

 

Correct me if I'm wrong, but the mere fact that the battery would accept such a charge rate was the point wasn't it??...not that it could be accomplished in many locales

 

A point being I have a 45litre fueltank in my car and the bowser has a capacity to pump fuel at 50litres a second:?:

 

Hi Masalai,

If that company will produce batteries of 12 Volt/ 2 -250 Amphr and you take 4 of them in series, this certainly will be the solution for you. You would have saved sufficient weight to be satisfied. It will make me (personally) much happier in you not having batteries parallel.

Bert

 

Thanks Bert,

I am constrained by the criteria that I need to be able to lift them out and return same in the event of needing to replace one or more so unit weight of around 20KG to an absolute maximum of 30KG tends to limit my options and the BMS for these Li derived batteries needs to mature, as does the actual battery - in reliability and redundancy and price could also be a significant factor as money is not limitless... The Li based systems are still in consideration - any links including price, unit weight, technical info and BMS system would be appreciated as and when they come to your notice...

Thanks again for your continued interest and dedication to your research...

 

Hi Masalai,

Misunderstanding. If 1200Ah at 12 Volt weighs 153 pounds = 73 Kg, it means that 200Ah at 12 Volt would be approx 73 : 6 = 12,2 Kg. You can lift that when you are 96. The price is the big questionmark. S... I just paid 545 dollars (USA) to get me something which may be outdated by the time I recieve them. Well, life is like that.

It should be easy to modify a Lead Acid battery plant to accomodate this new process. It is the selling price which worries me. But I bet that many other sealed lead acid and normal Lead Acid battery manufacturers will be lining up for a production license. Thus watch your local manufacturer. If he doesn't jump the bandwagon, he may have to close his company down.

Bert

P.S. maybe somebody will make this type lead acid battery in a type "D" can, it will solve my problem. I will then not have wasted all my effort. You, for sure will be able to lift a type "D" battery when you are 96.

 

Something is not right.

Maybe CDK is correct that we have a half star trek story.

12 Volt >>>>>>>>>>>>>>>>>> 12 Volt ratio 1: 1 = O.K.
170 Amphour >>>>>>>>>>>>>> 1200 Amperhour = ratio 1 : 7,05 = O.K.
117 lbs >>>>>>>>>>>>>>>>>> 153 lbs = ratio 1 : 1,3 ???????
17,44 Wh/Kg >>>>>>>>>>>>>>> 94,12 Wh/Kg = ratio 1 : 5,39 ??????

Can you help me out? I am puzzeld. Something is not right.

Bert

 

Just before I fell asleep, going over the problem, I realised where the error was. ratio weight = 1 : 1,3 times ratio 1: 5,39 = 1 : 7,00 which is thus correct. But what is not correct, the 17,44 Wh/Kg and 94,12 Wh/Kg should read 17,44 per pound. This is fantastic if they can materialise this. It means 94,12 Wh/pound = 207 Watthour per Kg. My LiFePO4 will only give me some 62 Wh/Kg

Masalai, 4 x 12 Volt batteries in series of 200 Amperhour = 9,6 Kwh with a weight of +/- 50 Kg. You could easy put 4 banks there and your weight is only 200 Kg, but you would have 38,4 Kilowatthour. But please don't put batteries parallel. Keep the banks seperate and just switch over with an automatic switch from one bank to another if the Voltage becomes at a certain lower level.

This new technology would save the present battery industry. Anybody who wants to buy my 40 LiFePO4 ??

Bert