Converting a HiSun Sector E1 to Lithium

[Sun Fun Kits]

Hello,

recently we converted a HiSun Sector E1 to Lithium Iron Phosphate batteries. The batteries now have 16.4 kWh (315 AH) of capacity, 24 horsepower peak, and it reduced the weight of the unit by 360 lbs. We were able to use the same onboard charger but did upload a lithium profile to it. We also needed to add custom battery trays. The conversion process is explained below in this video:

 

 

We also now have a 4 port supplement charger option for those wanting a dedicated charger or are using 1 of the batterie to run a winch/snow plow with more power requirements:

 

Finally we wanted to show cold weather use and how the unit can be setup to perform regen in the cold without problems as the batteries can regen and stay warm:

 

[hdtran]

Nice video!

My E1 (2022 model, has the DeltaQ charger and the manual claims that it has the Sevcon Gen4) has been driven less than 60 miles in two years--I don't anticipate doing more than 30-40 miles a year, as it's mainly to go around our 8 acres to pick up downed trees, etc. The one time I decided to go to the local stores, it's 5 miles each way. It's downhill all the way to town, and uphill all the way back. The E1 struggled on the steady uphill--It started throwing low voltage errors, to the point where I had to stop and let the original batteries rest a few minutes, then go for a few minutes, repeat... The last two miles uphill are an average 7% grade, with some sections hitting a 10% grade.

I would add that once I got home, I "tested" each battery using a Harbor Freight battery tester. Each of the lead-acids took a 100A draw from the tester for a few seconds without dropping huge amounts of voltage--so no one single lead-acid was bad. They just collectively could not handle the long continuous uphill.

The question is: Most of the hills that I saw in your testing in the video were pretty short hills. How much current was it using on the steeper pitches? Can I drive for 8-10 minutes at a 200A draw (what I estimate I'd need to go between 10-20 mph uphill) without triggering a "too much current draw" with the series connection of your battery packs?

[Sun Fun Kits]

Hi

Our kit will allow you to draw 350 Amps for 50 seconds continuously, after that it will issue you a warning (this can be adjusted in the app, you can change it from 10 sec to 50 sec).

As for AMPS, please note many people assume amps from lead are the same as lithium when it comes to use. This is not correct what you need to see is the watts from lead vs watts from lithium:

In our video we show it takes 200 amps from lead acid to run at full power:

 

In contrast to do the same on lithium it only takes 120 amps:

So this does not mean the amps on lithium are more powerful than lead, it just means you are able to get the same watts from lithium at far less amps than on lead because the voltages do not drop on lithium.

Our kit is also 3x the capacity of most lithium kits, these are usually 105AH, ours is 315Ah, the larger cells exhibit even less voltage drop.

Remember watts = volts * amps.

That being said in lemans terms, if you are using 200 amps on lead acid, you will be using 125 amps on lithium to do the same task on average. At 200 AMPS on lithium its roughly the same amount of power as 350 amps on lead.

So you should have no issue climbing the hills (we are fairly flat part of the country so only small hills here).

Remember, the contactor on the E1 is only rated for 200 amps continuous so its more likely the bottle neck will be drive train on the E1 before the batteries, we have over 400 conversions with our kits on the Polaris ranger and about 15 on the E1.

Eventually we plan on releasing a 400 AMP continuous, 1200 burst kit with 4x 24v (2S2P setup) batteries but that is only for people that are going to modify the unit with upgraded motors and  upgraded speed controllers, it not recommended for stock controllers and motors because in our testing we saw no difference in performance between 4x12v (4S) or 4x 24v (2S2P).

 

 

[hdtran]

Understood, it's the power (watts). Amps are more directly related to torque, at least for DC motors.  I didn't think that the lead-acid had that much of a voltage drop at higher currents.

The motor temp monitor on the dash climbed as I was going up the continuous grade. At one point, a different error message came up (not 45C3, the low voltage error, which appeared a lot during the climb), and I had to just stop and wait for a few minutes before I could continue. I understand the controller has temperature sensors, and will try to keep my motor from overheating--but if it hits 80F in the mountains, it's a heat wave!

What's the maximum continuous current draw (with a flat voltage curve, that'll be proportional to power) from your lithium batteries?

315 A-h (or if I only go to 15% max depth of discharge, effectively about 270 A-h) is more than enough range for me--I could pick up all the dead trees in our property without a single recharge all summer!

Obviously, I'll have to deal with much colder weather than in Louisiana. I won't be driving the UTV much in winter--in a good snow year, it'll get snowed in, and won't emerge until spring--but storage temperatures will routinely hit 0F, and frequently -10F at night. I can keep the unit plugged in, unless we get a power outage 😉 . I think that's my other big concern--our average last frost date is around Memorial day, and they encourage not planting tender plants until end-of-June! And first freezing night can occur as early as Labor day!

We're at higher altitude, the valley floor is around 8500-8600 feet. In the winter, they have a temperature inversion. In the valley, it may hit -20F, but at my altitude (about 9300 ft), 0F, is the typical low in the winter night.

[Sun Fun Kits]

This is the contactor on the Hisun E1: https://noco-evco.com/product/SW180B-108.htm

If you read its only rated for 150A for inductive (electric motors) load. So already with Lead we are pushing it harder that it supposed as we have to compensate for the voltage drop. In contrast with lithium because ware able to keep the voltage up we are able to stay with in the current inductive load limit of the contactor.

The official HISUN part is number for this is: PDDC001377450000

The batteries we have will let you push the E1 to its maximum capability, but it will not increase the machines limits, if the job you are asking for exceeds its maximum limit than regardless of what power source you choose you will run into the same situation and will need to upgrade the controller, motor, contractor and other components until it can meet your demands.

 

NOTE: with our many Polaris Conversions we find the same weak link, pushing the unit hard results in the contactor burning out, rarely it is the batteries. In our internal tests our batteries are able to provide 400 amps for 30 mins before BMS failure.

[hdtran]

I greatly appreciate the technical details that you're giving me! I've got a section of hill about 1200 ft long with a 100 to 120 ft rise (according to Google Maps, anyway) right next to my driveway. I'll do some driving tests on that hill in the "M" (max range) setting, and pay attention to the gauges.

[Sun Fun Kits]

Based on the description, you are describing a 10% grade road. At full power the unit would be able to complete the distance in 32 seconds at 24.5 mph it would be with in the 50 second limit we put on the batteries and would allow up to 350 amps for that duration.

Note: it may put stress on your motor & contractor though, we have customer running on longer hills with higher grades without issue.