# Tata nano Ev conversion



## RIPPERTON (Jan 26, 2010)

dawg_gone said:


> Its one of the smallest cars in the world, yet it caters to 5 people.


As long as they are midgets. 


Here is a good motor I have tested this to 34kW and 196Nm at the wheels with a 5.5:1 differential. You will need to add air cooling
http://kellycontroller.com/kl-9000m-72v9kw-bldc-motor-p-1289.html.

http://kellycontroller.com/khb1440124-144v400aopto-bldc-controllerwith-regen-p-832.html
This ctlr will do for 175v or 52 series LiFePo4 for 136kmh with the 5.5:1 diff.
(Daihatsu Terios) For 200km range you will need 18kWh and regen.


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## RIPPERTON (Jan 26, 2010)

Its layout is a lot like the Smart


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## TheSGC (Nov 15, 2007)

Several years ago I converted a Tata Nano at a university in India. I used a ME1003 PM motor running at 72v using lead acid car batteries. It went about 32km on a charge and had a top speed of 100 km/hour. It was an extreme budget build, with less than $2k USD in parts.


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## dougingraham (Jul 26, 2011)

With any conversion the hardest and probably the most important thing to figure out is the batteries. If the vehicle stays the same weight after the conversion you would need approximately an 18 kwh battery pack to reach your 200km goal. An 18 kwh pack will weigh around 180 kg. That plus the motor/ controller and all the fiddly bits nobody thinks of will add some weight to the vehicle. Because of the additional weight, and the desire for the battery to have a long life, and the desire to still go 200 km when the battery starts to degrade you will need to oversize the pack. Doubling it would almost do it giving a 36 kwh pack that weighs 360 kg. Now you have a vehicle that can carry one person 200 km with not much room or ability to carry anymore weight.

The 18 kwh pack originally proposed will take you 100 km and the vehicle will weigh only a little more than it originally did. You would most likely be able to still carry 4 people. Trying to increase the range to 200 km is going to be both expensive and an exercise in frustration. A 100 km range is a practical goal.

As for AC motors, with a 100 km range you could probably get by with an HPEVS AC35 but I would go with the AC50 frame with the 144 volt Curtis controller in either case. This would limit the cell count to 46 cells and to get the 18 kwh I proposed earlier you would need at least 122 ah cells. Using pairs of 60 ah cells would probably be close enough. So a pack of 46S2P 60 ah cells would give a pack capacity of 17.7 kwh (46*3.2*2*60). If you want to try for more range you can try to figure out where you would put a 46S4P pack of 60 ah cells. This would be a little shy of the desired range but not too much. It would weigh more than 368 kg. The dimensions of a 60 ah cell (using the CALB numbers) 248mm high by 115 mm wide by 41 mm deep. Each cell has a volume of 1.17 liters so the small pack displaces 92 liters the large pack would displace 184.

Your goal of a 200 km range is at the limit of being practical. The problems are that the batteries will weigh too much, and take up too much room in the vehicle. You can do it but then the vehicle would end up as a two seater with no cargo capacity and it would most likely handle poorly too.

With a 100 km range you will still be able to carry several people and the car will probably out perform the original ICE powered version.

Best Wishes!


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## dawg_gone (Jun 5, 2013)

@ripperton thanks for the quick reply . Yes it is like smart.If you know any prior builts on this plat form do post a link

Also wont the stock Aircon system work as it is or i need to make changes to tht too?

@TheSGC Can you give me more details on this? I might wanna pursue diff ways to look at it.

@dougingraham thanks for the detailed entry. learnt quite a few things.I plan to lay the batteries on the base of the car so room for the batteries wont be an issue.the weight and handeling is what bothers me.The car is usually used by 2-3 ppl max. Also can you post me a link as to where i can buy the batteries,controllers and motor?


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## dougingraham (Jul 26, 2011)

dawg_gone said:


> @dougingraham thanks for the detailed entry. learnt quite a few things.I plan to lay the batteries on the base of the car so room for the batteries wont be an issue.the weight and handeling is what bothers me.The car is usually used by 2-3 ppl max. Also can you post me a link as to where i can buy the batteries,controllers and motor?


You are welcome. I am somewhat uncomfortable recommending places to buy parts. However the vendors who advertise on the right side of the forum screen are good places to shop. I would also look at the EVTV.ME store. The prices are a few dollars more but they have the items in stock and generally include everything you need to make that part work.

Good luck with your build!


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## dawg_gone (Jun 5, 2013)

Thanks a ton. Can you explain 46*3.2*2*60 this formula? Also the rating of the battery should be 122 Ah or 18 Kwh .I know its something stupid im asking but kinda confused. Also you said we can pair a couple of 60Ah , so by that logic can we also pair four 30Ah in series?


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## Duncan (Dec 8, 2008)

Funny thing is the Tata Nano is bigger than the old Mini!

2 inches longer
4 inches wider 
and ... 12 inches taller!


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## dawg_gone (Jun 5, 2013)

Duncan said:


> Funny thing is the Tata Nano is bigger than the old Mini!
> 
> 2 inches longer
> 4 inches wider
> and ... 12 inches taller!


Yes its very spacious!Im 6 feet 4 myself and its a very comfortable ride for me


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## dougingraham (Jul 26, 2011)

dawg_gone said:


> Thanks a ton. Can you explain 46*3.2*2*60 this formula? Also the rating of the battery should be 122 Ah or 18 Kwh .I know its something stupid im asking but kinda confused. Also you said we can pair a couple of 60Ah , so by that logic can we also pair four 30Ah in series?


In 46 * 3.2 * 2 * 60 = 18Kwh

46 is for 46 cells. 46 is chosen because that gives the maximum voltage (46 * 3.2 = 147.2 nominal pack voltage) usable by the high voltage Curtis AC motor controller (1239.)
3.2 is for the nominal cell voltage of 3.2 volts.
2 is for the pairing of two cells in parallel which will double the amp hour capacity.
60 is for the 60 amp hours of the batteries.
That formula would give watt hours and the actual number would be 17764 watt hours. Kilo watt hours is 1000 watt hours and is a more convenient representation so I rounded it up from 17.764 kilowatt hours to 18 kwh.

The desire for 122 ah would come from the 18 kwh divided by the nominal pack voltage of 147.2 (18000 watts / 147.2 = 122.3 amp hours). Strictly speaking this should be 17764 kwh / 147.2 = 120.7 amp hours. The equation is volts * amp hours = watt hours. So watt hours/ volts = amp hours. In any case you are looking for a cell that is close to 120 amp hours. There is no common cell sized 120 ah but you can parallel 60 amp hour cells to make a 120 ah cell.

If you could find 30 AH cells you could parallel four of them to make a 120 ah equivalent sized cell. Paralleling cells which means connecting the positive terminals of all four cells together and connecting all four negative terminals together multiplies the amp hours by the number of cells but the voltage remains the same thus increasing the capacity. If you place the four cells in series the amp hours remains the same but the voltage is multiplied by the number of cells.

So my suggestion for a 46S2P pack of 60 AH cells gives a total cell count of 46 * 2 = 92 cells of size 60 amp hour. In your 30 amp hour suggestion this would be a 46S4P arrangement. 4 * 30 AH sized cells in parallel gives 120 AH. If you then take 46 of those 4 cell modules and place them in series you will have a pack equivalent of 147.2 volts and 120 amp hours which gives a pack of 17764 watt hours or 17.764 kwh which could be rounded to 18 kwh.

The next question should probably be where the heck did the 18kwh goal come from? And that number comes from a simple rule of thumb where if you take the weight of the vehicle in pounds (1320) and divide it by 10 you get an estimated distance the vehicle can travel which we call watt hours per mile. In this case your vehicle is a light 1320 lbs adding in the estimated weight of a person so you come up with 145 wh/mi. Since your goal was 200km and that equals 124 miles and the rule of thumb is 124*145 = 17980 watt hours. This would have an exhausted battery at 124 miles on a good day when the battery is brand new. If you double this to take into account for using only 80% of the battery on a normal day to increase the life of the battery and then increase it again so at the end of 10 years the battery can still go that 200 km on a charge and then increase it again for cold weather driving and using the heater you end up doubling the size to 36 kwh. I proposed a more modest goal of 100 km and that cuts the necessary size of the battery in half.

Does that help?


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## dawg_gone (Jun 5, 2013)

dougingraham said:


> In 46 * 3.2 * 2 * 60 = 18Kwh
> 
> 46 is for 46 cells. 46 is chosen because that gives the maximum voltage (46 * 3.2 = 147.2 nominal pack voltage) usable by the high voltage Curtis AC motor controller (1239.)
> 3.2 is for the nominal cell voltage of 3.2 volts.
> ...


Thanks for the explanation.Solved all my queries.I really appericiate it. ill keep updating the progress of my vehicle


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## newbiebiker (Jul 1, 2015)

any update..??
as i also planned to convert tata nano to electric, actualy hybrid without replacing its IC engine.


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## MyECar (Sep 16, 2018)

hi, found this thread in a recent search; any progress / success with these attempts? pls let me know where to source the components. 


newbiebiker said:


> any update..??
> as i also planned to convert tata nano to electric, actualy hybrid without replacing its IC engine.


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## MyECar (Sep 16, 2018)

Could you pls provide info on where to source the components?


TheSGC said:


> Several years ago I converted a Tata Nano at a university in India. I used a ME1003 PM motor running at 72v using lead acid car batteries. It went about 32km on a charge and had a top speed of 100 km/hour. It was an extreme budget build, with less than $2k USD in parts.


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## [email protected] (Jul 2, 2018)

newbiebiker said:


> any update..??
> as i also planned to convert tata nano to electric, actualy hybrid without replacing its IC engine.



Hybrid, in my opinion, would be a lot harder unless you would want to use what Protean is doing by using INWHEEL motors. 

Else like suggested using the above systems would help you to convert a regular to an EV. 

Word of Caution : When you start playing with voltages above 48V remember, its enough to kill you if precaution is not taken. 

Do know your AWG's for wiring harness.


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