Chevy Volt Lithium Battery Packs Converted to 12 Volts. What you see is my 800 Amp Hours battery pack, with a weight of 188 lbs. It will change my Six Trojan T-105 (675 Amp Hours) with a weight of 384 lbs.
Hi Folks,
My six Trojan T-105 Golf Cart Batteries are are six years outdated, and working out of gasoline. I wished to substitute them with Lithium Batteries, but they don’t seem to be low-cost. Reading up on Lithium Batteries, I found the three things will greatly scale back the lifespan of Lithium batteries. 1) Letting the batteries discharge to far, 2) over charging them, and 3) letting them get to hot.
I picked up four Chevy Volt Lithium Battery Packs transformed to 12 Volts each rated at 200 AH. The batteries have liquid cooling, which I plan to make use of. The batteries even have a temperature sensor, so I might be able to monitor the battery temperature. There really isn’t any off the self Battery Management Systems (BMS) that can work with Chevy Volts batteries outdoors being in a Chevy Volt. The little I may discover out was that very max cell voltage is 4.2 volts per cell; nevertheless, in case you charge them that high, you’ll shorten the lifespan to lower than 4-5 years. Charging the batteries to 4.02 volts per cell, the batteries will final 15-20 years. Charge them to 4.1 volts per cell, and the lifespan drops to 7-8 years.
I have not found any information on max temperature, but some folks say keep them beneath 90 levels. I plan to keep my battery cell voltage between 3.Three Volts and 4.01 Volts, which I can regulate in the program, once I get some real world use.
Speaking of program, my BMS is house grown, using Arduino Mega microprocessor.
Arduino Mega Microprocessor 256 KB Memory sixteen Analog Inputs and 54 Digital Input/Output Pins
I added off the self Ethernet board that plugs right into the Arduino, and i added two prototype boards with my circuits to measure cell voltage, battery temperature, total battery voltage and Boostcaps voltage.
In case you surprise what a Boostcap is, here you go, I’ll explain later why you want them.
Top and facet view of my BMS. Four ribbon cables will attach to the two prototype circuit boards. I nonetheless have to wire the fan. Pump control pieces. I will use two MOSFIT so I can management the velocity of the fan and pump.
Here is the side view of my four Chevy Volt battery packs. Two packs are linked collectively to make two 400 AH battery packs.
Battery Management connections. One for every pack.
That is my improvement work in progress. The very top you will see the Boostcaps (six in collection). The entrance middle you will note the battery relay. To the right of the battery is my BMS, and LiFePO4 battery to the correct of that is passion battery monitor, balancer, and discharged.
Here is two packs related to the BMS.
Here is the Battery Management System internet page I programmed for the 2 battery packs above.
Here is the accomplished BMS internet page, with batteries not related.
Ok, so the why do we want the Boostcaps? There two causes, the photo voltaic controller is not actually made for Lithium batteries, and neither is the Montana’s converter (converts a hundred and twenty volts AC to 13.5 Volts DC). Lithium battery will cost a very excessive price, however after they attain the cost voltage, it’s worthwhile to cease charging them. The most typical RV batteries are Lead Acid, AMG, and Gel batteries, lithium battery buy which you’ve gotten to carry a high voltage of charge for 3 hours to totally cost them. These sort of batteries require 15% more energy put into them, than you get again out. Should you loved this informative article in addition to you desire to acquire more information with regards to lithium battery buy generously go to our own web-site. Also only 50% of AH capacity can be used. The number of cycles is round 500.
With Lithium batteries, you get the identical quantity of energy out as you set again in. Lithium batteries can safely use 80% of AH capacity, and number of cycles is 3,000 to 4,000. If not pushed past the 4.02 volts per cell, battery temperature maintained, the batteries might last 15-20 years.
The drawback to Lithium batteries, is you will need to have special charging methods that manages the charging, discharging of the batteries, and keeps the cells balanced.
So now we come to the Boostcaps, to trick the dummy charger into considering it’s charging a Lead Acid battery. The Boostcaps are very low voltage (2.7V) so putting six in collection the can handle 16.2 volts with hundreds of thousands of cycles. I don’t know how many Amp Hours are in the Boostcaps, but the can ship 1,000 Amps for brief time frame, and recharge in seconds when related to a battery.
Since the solar controller will be damaged if disconnected from the batteries whereas the photo voltaic array is making energy, the Boostcaps provide a battery like equivalent, and everyone seems to be happy.
Now we’d like a manner to attach the batteries to the Boostcaps when the batteries need charging, lithium polymer battery pack and to disconnect when totally charged. And if the Boostcaps voltage drops below the battery voltage (meaning no more photo voltaic energy or load is larger than photo voltaic output), we want to connect the batteries to recharge the Boostcaps. We additionally need to verify no battery cells drop below the set worth in the BMS parameters.
Battery relay is controlled by the Arduino program, which screens all of the batteries cells, battery voltage, and Boostcap voltage. This system will then decide weather the relay ought to be closed or not.
Here is the Arduino, with my two prototype boards and the battery balancer. When all four packs are hooked up there can be four battery balancers plug into the 2 prototype boards.
Although I’ve already prototype’d the Fan, Pump, and Heater controls, I need to place these circuits my completed prototype boards.
I also want to construct a insulated battery field to keep batteries heat. After that I will need to plumb the cooling traces, pump, and radiator to keep then cool.
A pair people have requested how the batteries had been converted to 12 Volts. I bought them already converted, but mainly the cell connection plates are minimize into sets of three cells in series. Then the four sets are wire collectively in parallel.
Battery heat, pump and fan circuit. Here I have just the Boostcaps related so I. Test the brand new circuits I constructed tonight (2-23-2016). Also test low. High voltage disconnects. The light will be my heat source.