Rupert_Baehr Posted January 6, 2011 Share Posted January 6, 2011 If they're anything like the lightbulbs that are quoted to last 8000 hours, they'll be no better than the current crop. No pun intended. They work - and they will recharge 8000 times. At present, they are very heavy, but efficiency is improving by about 30% each year. (A friend of mine is involved in the r&d) and within a couple of years he predicts they will weigh no more than (and be no more bulky than) Lithium-Ion batteries of the same capacity. That assumes that the battery is used over a large percent of it's capacity. The Prius for example only ever runs the battery between something like 35% and 60% charged (not sure what the exact figures are) which increases the number of charge/discharge cycles enormously. Fork lift trucks sometimes do the same sort of thing - they can have a 15 year battery life on some models despite being in daily use. Yes, but the Prius is a hybrid. When more efficient batteries with a higher Power: Weight ratio become readily available, then electric (as opposed to hybrid) cars should become more viable. Another poster mentioned changing batteries out at a garage. Consider the following scenario: Mr A buys a brand new electric car (fitted with Lithium Ion batteries) on Monday. On Tuesday (after he's taken the car out for a drive) the batteries start to become discharged as he is aproaching a garage (which operates a battery exchange.) He pulls into the garage, his brand new (but discharged) battery pack is exchanged for a fully-charged replacement. That fully-charged replacement was about 5 years old. What was his car worth on Monday? What is his car worth on Tuesday? Link to comment Share on other sites More sharing options...
danny11 Posted January 6, 2011 Share Posted January 6, 2011 Whats the point when a fiesta/polo diesel will do over 60mpg round town, free road tax and cheap to buy new Link to comment Share on other sites More sharing options...
Obelix Posted January 7, 2011 Share Posted January 7, 2011 They work - and they will recharge 8000 times. At present, they are very heavy, but efficiency is improving by about 30% each year. (A friend of mine is involved in the r&d) and within a couple of years he predicts they will weigh no more than (and be no more bulky than) Lithium-Ion batteries of the same capacity. Yes, but the Prius is a hybrid. When more efficient batteries with a higher Power: Weight ratio become readily available, then electric (as opposed to hybrid) cars should become more viable. Another poster mentioned changing batteries out at a garage. Consider the following scenario: Mr A buys a brand new electric car (fitted with Lithium Ion batteries) on Monday. On Tuesday (after he's taken the car out for a drive) the batteries start to become discharged as he is aproaching a garage (which operates a battery exchange.) He pulls into the garage, his brand new (but discharged) battery pack is exchanged for a fully-charged replacement. That fully-charged replacement was about 5 years old. What was his car worth on Monday? What is his car worth on Tuesday? It depends if you treat the battery pack as an asset - if all it is is a means of buying another 200 miles and it's always swapped at recharge time, it's more or less irrelevant to the age. Say you pulll in and buy a recharge. You pay for say 100kWh and are given a battery that has that much charge in it. It doesnt matter if that's 50% charged or 90% charged - you have the 100kWh you bought. The next time it'll get swapped again. The battery is irrelevant as long as this happens each time. Where it does matter is if you also charge at home - then you may have a problem. Personally I'd like to see filling stations turn into battery stations where you exchange them and they are recharged - you can then add in the necessary infrastructure as HV supply to reduce transmission losses. The cost of battery degredation is obviated by means of a small charge on the electricity that you are paying for in the charge costs as it were and no-one has to buy a battery ever - it just becomes a removeable fuel tank. Link to comment Share on other sites More sharing options...
Treatment Posted January 7, 2011 Share Posted January 7, 2011 Whats the point when a fiesta/polo diesel will do over 60mpg round town, free road tax and cheap to buy new hyblid car velly god flor honoulable envilonment Link to comment Share on other sites More sharing options...
Rupert_Baehr Posted January 7, 2011 Share Posted January 7, 2011 It depends if you treat the battery pack as an asset - (A) if all it is is a means of buying another 200 miles and it's always swapped at recharge time, it's more or less irrelevant to the age. Say you pulll in and buy a recharge. You pay for say 100kWh and are given a battery that has that much charge in it. It doesnt matter if that's 50% charged or 90% charged - you have the 100kWh you bought. The next time it'll get swapped again. The battery is irrelevant as long as this happens each time. (B) Where it does matter is if you also charge at home - then you may have a problem. Personally © I'd like to see filling stations turn into battery stations where you exchange them and they are recharged - you can then add in the necessary infrastructure as HV supply to reduce transmission losses. The cost of battery degredation is obviated by means of a small charge on the electricity that you are paying for in the charge costs as it were and no-one has to buy a battery ever - it just becomes a removeable fuel tank. A 100KwH battery? How big is that going to be? A 288v 70AH Lithium Iron Phosphate plug-in battery (roughly 20KwH) weighs 315Kg. Its dimensions are 450*1650*335mm. You'd need 2 or 3 people with specialist lifting and moving gear to fit one of those. I don't know how many batteries a trained team of 3 people would be able to change in a day, but garages would suddenly have a lot of jobs to fill and the line to 'fill up' your car would get pretty long. (A) & (B) - Precisely. But some people will charge the battery at home (that, after all, is where most of us keep our cars), some will never use a replacement service (particularly low-mileage drivers) and some will use a replacement service almost exclusively. I suspect that the costs at © might turn out to be rather higher than one might think. I don't know what the average fill-up for a petrol-engined car is, but let's assume it's 40 litres and that 40 litre fill would take the car 300 miles and the owner fills the car every 2 weeks. If a battery pack wil take a car 75 miles, you'd need 4 battery changes for every 40 litres sold. How many litres of petrol does a small rural garage sell per day? How many litres does a service station on a motorway sell per day? How many litres does the filling station at a local Tesco sell per day? Divide those figures by 10, and that will give you an idea of how many charged battery packs rural garages, motorway service stations and supermarket filling stations will need per day. Where are you going to store all those battery packs? Where are you going to recharge all those battery packs? Who is going to pay for the battery packs each garage will need as working stock? How are you going to shift battery packs around in the event that a garage runs out? How many employees are you going to need to change a battery pack? - How much will you have to charge a car owner each time (s)he wants a pack exchange for labour, return on stock cost investment, plant, storage costs, etc? On top of that, you've still got the cost of the electricity itself. Would £30 a time (plus, of course the cost of the electricity used to charge the battery) cover it? Link to comment Share on other sites More sharing options...
wednesday1 Posted January 7, 2011 Author Share Posted January 7, 2011 Thanks for your contributions. Plenty to think about! Link to comment Share on other sites More sharing options...
Obelix Posted January 7, 2011 Share Posted January 7, 2011 A 100KwH battery? How big is that going to be? A 288v 70AH Lithium Iron Phosphate plug-in battery (roughly 20KwH) weighs 315Kg. Its dimensions are 450*1650*335mm. You'd need 2 or 3 people with specialist lifting and moving gear to fit one of those. I don't know how many batteries a trained team of 3 people would be able to change in a day, but garages would suddenly have a lot of jobs to fill and the line to 'fill up' your car would get pretty long. (A) & (B) - Precisely. But some people will charge the battery at home (that, after all, is where most of us keep our cars), some will never use a replacement service (particularly low-mileage drivers) and some will use a replacement service almost exclusively. I suspect that the costs at © might turn out to be rather higher than one might think. I don't know what the average fill-up for a petrol-engined car is, but let's assume it's 40 litres and that 40 litre fill would take the car 300 miles and the owner fills the car every 2 weeks. If a battery pack wil take a car 75 miles, you'd need 4 battery changes for every 40 litres sold. How many litres of petrol does a small rural garage sell per day? How many litres does a service station on a motorway sell per day? How many litres does the filling station at a local Tesco sell per day? Divide those figures by 10, and that will give you an idea of how many charged battery packs rural garages, motorway service stations and supermarket filling stations will need per day. Where are you going to store all those battery packs? Where are you going to recharge all those battery packs? Who is going to pay for the battery packs each garage will need as working stock? How are you going to shift battery packs around in the event that a garage runs out? How many employees are you going to need to change a battery pack? - How much will you have to charge a car owner each time (s)he wants a pack exchange for labour, return on stock cost investment, plant, storage costs, etc? On top of that, you've still got the cost of the electricity itself. Would £30 a time (plus, of course the cost of the electricity used to charge the battery) cover it? I dont claim to have the answers, but what I'm proposing is a reason why with battery exchange you wouldn't care about the condition of the pack - as long as it can supply the energy you bought. People originally fuelled petrol cars at home - they either had the ironmonger deliver it via horse and cart, or they buoght in bulk themselves and stored and filled at home. The infrastructure costs are irrlevant - petrol stations want to go into business they have to fund the site, tanks, filling equipment etc etc. If you want to go into charging then it's just another cost that you add to the capital costs - the same with batteries. It does rather require a standard battery that is amenable to being exchanged automatically so you can drive in, wait for a couple of minutes whilst the robo arm removes and then fits a new pack and that will be a sticking point I suspect. Cost of charging - who knows. If electricity is cheaper than petrol and it's about a quarter of ther delivered price then it's an economic winner. Link to comment Share on other sites More sharing options...
euclid Posted January 7, 2011 Share Posted January 7, 2011 My mate has a prius. Very quiet, drives like a petrol car (mainly because on the bits where you need power, the petrol takes over), low if not no road tax, and free parking round sheffield. He has a special badge that the council give to hybrid drivers allowing them free parking in any council car park or space. He didn't get stuck in the snow at all either. And he can drive from crookes to work in town on zero fuel. Down side - the car was expensive to buy and I dont really like the look of it. The Prius is also a hybrid and i believe the road tax is nil for them,when extra power is needed(accelerating etc) the electric motor (20bhp on Honda civic hybrid) comes in to assist the petrol engine (IMA...integrated motor assist),the batteries are recharged when slowing down and braking,these have a Honda eight year waranty...the Prius is expensive though from around £21,000-£26,000 Link to comment Share on other sites More sharing options...
mike84 Posted January 8, 2011 Share Posted January 8, 2011 I've driven a Prius recently. Awful car, rubbish build quality, poor fuel economy and has stupid auto gearbox. Steering wheel didn't feel like it was actually connected to the wheels Over the 3 weeks I was unfortunate enough to have one I averaged 42mpg. This includes town, motorway and A/B road driving. Any modern diesel would have returned better economy and performance. It's not a motoring experience I'd like to repeat! Link to comment Share on other sites More sharing options...
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