8 kWh 2011 Zero BATTERY projectSTOCK ACTUAL SETUPMy stock DS 2011 is giving me 60 real Ah measured capacity before it cut.
That is with 50% highway and 50% city wich correspond to my average use.
This is giving me 60km range most of the time.
I can easy conclude that each Ah is about 1km range
But since the last Ah of a discharged battery represent less energy than the first Ah, it is better to calculate Wh ( What hour) energy wich is not dependent to voltage.
ex: from 0 to 1Ah consumed at 58V this is 58Wh energy
But with the battery at 46V ( near empty) the ah from 59Ah to 60Ah mean only 46Wh wich is 20% less energy for this last Ah
So let's now talk with What hours
My stock battery measured full energy is 3000Wh so with 60Ah the average voltage is 3000/60 = 50Volts.
Adding 5kWh of A123 LiFePO4 cells!!! The phase 1 of my project consist of using 32 of my A123 LiFePO4 pouches for the first 2kWh addition.
I choosed these A123 LiFePO4 battery because:
- They have excellent reputation and specs,
- Can charge in 15 minutes
- Have 2000cycle of life compare to LiMn
- I already have alot of hardware for 16s ( 48V(52V) standard)
- 16s LiFePO4 match the stock 14s LiMn voltage range
- They have awsome power ( 20 to 30C continuous)
- They are more compact than the LiMn Molicells
That first phase of the project consist of adding 40Ah of LiFePO4 wich will give about 40 more km range wich will extend to 100km ( 50% city 50% highway) wich is a great beginning.
THe big problem is finding the right room to locate them.
After many reflection i decided that the stock 900W quick charger is too big and have to be replaced by something more compact that i can cary or not ( not permanent on the zero)
i'll buy a Meanwell RSP-2000-48 power suply wich cost the same as a quick charger and is 4 time more compact but have the same efficiency and cahrge 2.2time faster
295*127*41mm (L*W*H) and weight 2kg !!
http://www.trcelectronics.com/Meanwell/rsp-2000-48.shtmlThey can be placed on both sides of the actual zero battery, they enter perfectly in the frame and are really thin !
If i add alot of range in battery , the only time i'll need for recharge will be on a planned trip and i'll be able to decide to cary it with me in a bag.
Believe it or not, the room that the stock delta Q quick charger have is exactly the room i need to install the first 2kWh of A123 cells
Next phase will be to relocate and replace the controller. I'll install a Kelly 72V 600A model with regen. This controller is like half the size of the alltrax 48V 500A !
The Kely will be located under the seat neat the motor fan blower. It will still have short lengh cable and will be more accessible.
This will add room for another 2kWh, but this time the cellsl will be the 26650 cells ( same as in teh dewalt 36V cordless drill) I have about 320 of these cells that i carefully measured one by one after they was recovered from " deffective" toolpack. They will be in 16s20p config. The average Ah of these cells is 2.175Ah so this will give me 43Ah but i'll only use 40 to keep them balanced.
I plan on adding a common BMS with paralleled 16s balalnce connector that will connect to each 2kWh packs. ( as well i will ensure that all these packs will be connected in parallel only when their voltage is the same!
Now the great question you all wonder: Man... ? How will you connect them to teh actual electrical system ? The stock zero bms is 14s and your battery are 16s ?
Well, i'll only connect the main power connector in parallel, The added battery will have their own central BMS system of 16s.
I still wonder if i add a diode to both battery ( best would be a high current ideal diode made of mosfet) because i dont want to have one of the LIMn or LiFePO4 packs to overcharge a low cell due to connection loop because of the parallelling between both pack with their independent BMS.
Today i finished the first 2kWh made of pouch. I will add the connections and sealed enclosure later.
Another fact that is interesting is that i might get a bit more range due to the " peukert effect" wich mean a pack that is drained at lower current is giving a bit more Ah... so the stock zero battery i have that is giving 3000Wh might give let say 3250Wh because it will have less load due to the current share that will make each pack to have less current draw then when it's a single pack.
will see...
Here is my first 2kWh of cells
( one assembled and another not yet assembled)
Battery Fabrication ( YT video)
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Topic: Diy Battery Upgrade to my DS 2011 to add 100km range !! (Read 7635 times)