Hisun Sector e1 Battery replacement: any tips?

[EVSupport]

49 minutes ago, thom0329 said:

Thanks EVSupport. I don't understand how these are inadequate in power output. They have more output than almost any battery I've looked at. The only problem seems to be the lack of Battery Management.

You need a pack that under all conditions will cope with the max demands of the motor controller. If you ave a decent pack of a high Ah, its never under stress, that means lower heat, that means longer lif. When not being pushed to the limit a pack will hold its voltage up, if a too small pack is pushed the voltage drop will be much greater and more quickly show up poor cells. This is especially the case with cheaper lifepo4 which generally are not as good at holding voltage as Li Ion (Nickel, Manganeese, Cobalt ) So if you go for cheaper Lifepo4 always have enough Ah or more than the minimum.

 

[thom0329]

34 minutes ago, EVSupport said:

If you have a serial string its important that the BMS works across the whole string. If you connect parallel then they will work fine. If one pack has a cell thats high it will get bled down , that would pull the whole battery voltage down, but it would then be maintained by the parallel batteries, so they would also go down to the same level. Even without any bleed / balance connection between parallel strings. That cannot happen in serial strings and should not be done at any cost.

Now I'm not sure why the original 2 battery in parallel setup from Vevor wouldn't work. I've also found these batteries that explicitly states up to four in parallel.

https://www.temu.com/ca/48v-100ah-lifepo4-golf-cart-lithium-battery-5120wh-golf-cart-deep--external-lcd-data-monitor-built-in-200a-bms-with-low-temp-protection-ideal-for-marine-trolling-motors-etc-marine-battery-deep-cycle-power-highcapacity-battery-compact-battery-design-lithium-iron-phosphate-highefficiency-battery-battery-for-golf-cart-fishing-hobbyists-boat-owners-g-601103166369589.html?_oak_mp_inf=ELXe0eWz1ogBGiBiYzQ5NTMzN2Y4YzA0NzZkYmYxMTI5ZGFiZmFlOWIyYiDi69fAlzM%3D&top_gallery_url=https%3A%2F%2Fimg.kwcdn.com%2Fproduct%2Ffancy%2Fd5d7ddba-f003-465f-ae50-1ec3cd2a2e77.jpg&spec_gallery_id=17257769375&refer_page_sn=10009&refer_source=0&freesia_scene=2&_oak_freesia_scene=2&_oak_rec_ext_1=OTI2MzE&_oak_gallery_order=1817409394%2C1075432369%2C1645380346%2C425045480%2C2069271800&search_query=golf cart battery&search_key=golf cart battery&refer_page_el_sn=200049&refer_page_name=search_result&refer_page_id=10009_1758656321826_vhg4pm2v10&_x_sessn_id=iyeuyz6az2&is_back=1

[GNFO]

I can't access that link, but at least they say it can be wired in parallel.  If nothing else, the particular Vevor battery you pointed to before wouldn't have had any warranty support if you tried to wire more than one.  EVSupport is correct that there is less risk in parallel wiring than series, as they can eventually level themselves, but the risk isn't zero. Particularly if you are pushing the capacity of the batteries and they don't have time to self-level.

If the different batteries you're linking to can, combined in parallel, add up to more than 400A continuous output, you'll probably be fine.  Personally I still would want them to be able to cross communicate between their BMSs, but it will work without that.  Chances are you'll be fine, but their longevity will probably come down to how hard you push them and the quality of the batteries themselves.  A smart interconnected BMS helps reduce some of that risk.  In a way you can look at it like insurance, you may never need it, but you may also be glad you have it.

On a non-technical topic, please be sure the brand name of the battery you're looking at has good customer service reviews (that weren't generated by a bot).  I probably don't need to tell you that the wild west of Temu or AliExpress can be hit or miss.

[thom0329]

See below a better link to the batteries. Multiple units won’t communicate between BMS’s but it does state compatible with up to 4 in parallel. 

https://share.temu.com/ZmPlAIXpHRA

Obviously I’d rather have a higher quality battery but it’s diffficult to justify the added cost of comparable set up. One concern I’m having is safety. I have two kids who will be using the SXS. Do these cheap batteries raise any safety concerns?

[GNFO]

Temu has country-specific pages and that one won't come up for me.  But regardless I think you have the idea on the trade-offs.  The risk of course with any cheap battery is that it could turn into a brick in a year and you have to weigh cost vs risk. Mine were quite expensive, but it was early on in the development of the LiFePO4 battery market and they have a 10 year warranty with a full replacement with no pro-rating in the first 7 years.  They also were quick with technical support and provided their own custom made charging profile to update the Delta-Q charger.  Granted, I didn't have a lot of options at the time, but it's been worth it for me and I use the UTV all the time.  Would I go with something like the LiTime batteries if I were doing it now? Maybe...

From an actual safety standpoint the main risk from any high powered battery system is fire, even with the old Discover batteries.  I don't think it's a huge injury risk while the UTV is operating, in that you'll smell it right away and emergency egress from an open side-by-side is pretty easy. 🙂 The brakes are mechanical and will still work if there is a power failure.

Of course the other side of the fire risk is while they are charging and setting fire to something nearby like those e-bike battery fires that got attention in New York.  That was why I recommended finding any real reviews from people actually using them that you can. Even if you aren't going to buy them off of Amazon, sometimes these off-brands are also available there and you can look for those reviews.

I would hope batteries of this size, even the cheap ones, would be safer from that standpoint than small e-bike batteries, but if there are enough reviews that seem to be from real customers it should help ease any concerns.

[LAMA]

18 hours ago, thom0329 said:

Viz níže lepší odkaz na baterie. Více jednotek mezi systémy BMS nekomunikuje, ale je kompatibilní s až 4 paralelními jednotkami. 

https://share.temu.com/ZmPlAIXpHRA

Samozřejmě bych raději měl kvalitnější baterii, ale je těžké ospravedlnit dodatečné náklady na srovnatelnou sestavu. Jednou z obav, které mám, je bezpečnost. Mám dvě děti, které budou používat SXS . Vyvolávají tyto levné baterie nějaké bezpečnostní problémy?

This battery is intended for golf carts, where BMS 200A is sufficient. Sector (Vector) E1 can handle up to 400A, so BMS 200A will be a limitation. Also, there is no information whether this BMS 200A can also recuperate.

[Gorj]

On paper that may be so. But I have experienced no limitations. 

[Tommy2bits]

I have a 135ah LifePO4 single battery with 200a continuous and I climb very steep off road hills at home like a champ and get around 30 miles out of it before I hit 20%. At my lake community, my old golf cart would struggle and drop to 7mph while the machine doesn't even notice the long and steep paved roads. Using a 200a battery may not be fully utilizing the motor but it is definitely a limitation for me in power or longevity

[Jon Arne Pettersen]

 

Hello, interesting reading all your projects. 

 

Her is mine. 

 

I just bought a "new" 2023 model with only driven 10km 

Her is my project 😊

 

I hope I can get some feedback on this 👍

Hisun Sector E1 — 19S LiFePO4 Upgrade Summary
Vehicle: Hisun Sector E1 UTV (original 48 V lead-acid version)
Goal: Replace lead-acid pack with high-energy 19S LiFePO4 system to increase speed, efficiency, usable power and cycle life, while staying within safe limits of the Sevcon controller and drivetrain.
Battery System
Chemistry: LiFePO4 (LFP)
Configuration: 19S1P
Cells: EVE LF280K class (nominal 280 Ah, measured ~305 Ah batch)
Nominal cell voltage: 3.2 V
Nominal pack voltage: 60.8 V
Max charge voltage: 3.60 V/cell → 68.4 V pack
Occasional top balance: 3.65 V/cell → 69.35 V pack (not daily)
Low-voltage limit (daily): 2.8–2.9 V/cell
Emergency cut-off: 2.5 V/cell
Capacity: ~19 kWh usable (19 × 3.2 V × 305 Ah ≈ 18.5–19 kWh)
Peak discharge: >600 A capable (limited by controller and cabling)
Continuous discharge: ~300 A typical use
Power Electronics
Motor controller: Sevcon Gen4 Size 4 (LV)
Nominal voltage limit: ~69.6 V
Peak allowed slightly higher with internal cutback
Measured operating current:
Acceleration: ~300 A DC
Cruise at top speed: ~120–140 A DC
Peak mechanical power: ~18–20 kW estimated
Top speed increase: from ~45 km/h (48 V lead) to ~55–57 km/h at 19S
Charging
Charger: Adjustable 67–84 V LiFePO4 charger
Daily charge setting: 68.4 V CV
Charge current: 30–40 A normal, up to 60 A occasionally
Termination: current taper, no float
Temperature compensation: disabled (LFP chemistry)
Connector: Type 2 inlet used purely as 230 V AC connector (no EVSE / CP signalling)
BMS & Safety
BMS: ANT Smart BMS, 19S
Contactor: ≥300 A DC rated, 12 V coil
Precharge resistor: 100–300 Ω, 20–50 W
Main fuse: 400 A slow-blow (optionally 450–500 A)
Cabling:
Drivetrain: 35–50 mm² copper
Charger: 16 mm²
12 V system: 6–10 mm²
12 V System
DC/DC: 30–100 V → 13.8 V, 50 A isolated converter
Buffer battery: 12 V 80 Ah gel battery
Purpose: transient buffering, redundancy, stable 12 V rail
Cooling
Custom evaporative spray cooling on controller heatsink (washer fluid spray)
Maintains controller plate temp ~60–70 °C under heavy load
Motor and gearbox remain below 50 °C
Spray only active above ~15 °C ambient
Key Observations
Induction motor explains high startup current and relatively low cruise current.
Voltage, not controller limits, is the main determinant of top speed.
Lithium reduces voltage sag dramatically versus lead-acid, improving both acceleration and sustained speed.
19S is the practical upper limit for this Sevcon platform without going into HV variants.
Summary
The 19S LiFePO4 conversion transforms the Hisun Sector E1 from a low-performance utility platform into a high-efficiency, high-power electric drivetrain with significantly improved speed, torque, range, and thermal stability — while staying within safe electrical and mechanical margins.
This setup prioritizes:
Long cycle life
Electrical safety
Thermal control
Serviceability
Real-world reliability over extreme peak performance

[Gorj]

I would say that with 305 AH you should achieve your goal and some. I installed a 100 AH system on mine and have more power than I can ever use. The only issue I discovered is that the BMS does not like the brake regen and it cut off the battery. I deactivated the regen system and no more issue. I use a 12v @ 60ah AGM battery for the system's 12v accessories. There is a slight "ghost" currant drain from the Li batteries so I installed a 200 amp cut-off switch on the system.

[Alien10]

This thread is very interesting, thanks to all who contributed to the huge amount of information, researching a future project I find it very informative. 

One thing I am missing is the cost of these replacement batteries.   I see them all over the the place from $500 to $1200 (USD) each.  

Can anyone give an estimate of the number of replacement batteries they used and their cost?    That might help members make some rational decisions.

Thanks again for all the comments.

 

[Jon Arne Pettersen]

2 minutes ago, Alien10 said:

This thread is very interesting, thanks to all who contributed to the huge amount of information, researching a future project I find it very informative. 

One thing I am missing is the cost of these replacement batteries.   I see them all over the the place from $500 to $1200 (USD) each.  

Can anyone give an estimate of the number of replacement batteries they used and their cost?    That might help members make some rational decisions.

Thanks again for all the comments.

 

My project will battery cost around 2000$ with bms and a new charger 60 amp cost 250$ I'll do all y work my selve. I'll try to sell the original battery pack 

[Alien10]

I think the Hisum E1 came with 8 batteries of lead acid variety at least that is what I'm finding as I look at used Hisuns for sale.  I am a total novice on EV. Reading these threads is education before spending dollars.   I gather that the replacement batteries that are discussed require fewer than the 8 originals to provide roughly the same electrical power, maybe even more with fewer batteries.   Hope I'm correct in my interpretation. 

Just was wondering if I got a used  E1 with 8 original batteries how many replacement batteries would I need to plan on and roughly the cost of those. Yes, I'd also be doing 100% of the labor myself.    (thanks for mentioning your cost. ) 

 

 

[Gorj]

It seems that most everyone who does this has a different way of doing it. I replaced the eight 6 volt lead acid batteries with four 12 volt 100 amp lithium batteries. They have been installed over six months and have worked very well. I also replaced the Hisun charger with a lithium charger. I also installed a voltage meter in the dash to monitor the battery voltage. In the summer I charge it about once a week. In the winter I charge two or three times a week, depending on how much I use it. I sold the eight 6 volt lead acid batteries for $75. Was happy to get rid of them! Personally, I think Hisun should charge a bit more for the E1 and install lithium batteries in them instead of lead acid batteries. There are several companies selling EV side by sides with lithium batteries that are priced only slightly higher than Hisun!

[GNFO]

2 hours ago, Alien10 said:

I think the Hisum E1 came with 8 batteries of lead acid variety at least that is what I'm finding as I look at used Hisuns for sale.  I am a total novice on EV. Reading these threads is education before spending dollars.   I gather that the replacement batteries that are discussed require fewer than the 8 originals to provide roughly the same electrical power, maybe even more with fewer batteries.   Hope I'm correct in my interpretation. 

Just was wondering if I got a used  E1 with 8 original batteries how many replacement batteries would I need to plan on and roughly the cost of those. Yes, I'd also be doing 100% of the labor myself.    (thanks for mentioning your cost. ) 

 

 

There are a lot of factors in play. This thread has been going on for almost four years and the availability of replacement batteries has increased quite a bit over that time. What country you're in comes into play, too. We have people from Europe/UK, Canada, US, and Australia and the available selection can be very different.  Those in the US seem to have the greatest number of options. I did my conversion almost three years ago and at the time there were very few GC2 form-factor lithium batteries in the US market, and really only one maker that had 48V batteries with a high enough constant amp output to match the Hisun motor. You could probably spend anywhere from $1,500-$5,000 US depending on what combination of amp output, capacity, and form factor you're looking for. GC2 form was important to me so I could just drop in replacements without customizing the tray to hold a physically larger size battery, but some of the conversions here did do just that. You'll pay more for batteries that have cross-BMS connections so all the batteries "talk" to each other to optimize output and charging, but depending on your use that may not be necessary with batteries connected in parallel. Gorj got to 48V using 12V batteries wired in serial, I and a number of others went with 48V batteries and went for increased amp output and capacity by using (generally) four GC2 form factor batteries. Some of the conversions just used one or two very large form factor batteries. Most of us also added a digital readout. You just have to weigh your own local battery availability, cost, ability to customize, time, performance needs, and how long/far you want to be able to go between charges (capacity). For me, four 48V batteries that combine to 120ah and a continuous output rating of 400A has been great on my 6 acres of wooded property with lots of uneven ground and some fairly steep hills. I never get below ~70% in a day even when running a 120V inverter for power tools, but I also get to plug in the evening.  If you plan on going far into the wild for a few days then of course you will need more capacity.  If that includes heavy loads and steep hills you want to make sure your amp output is at least 400A.  By going with the 48V GC2 form batteries, I reasoned that if I later found I needed more capacity I could easily just add more batteries in parallel. I've found those four have been enough for me, but I can see how others would need more.  The good news is that there are a lot more options now than years past and you can customize your solution to you.

[John M in Louisiana]

@Jamie Wilson How's your E1 doing now since the lithium upgrade?! 

I'm thinking about taking on this project.  Amazon has a 4pack LiTime 48V 120Ah (4-Pack 48V 30Ah) GC2  for $1,359.  

How do you go about doing an algorithm update for the original charger?  

[Jon Arne Pettersen]

9 minutes ago, John M in Louisiana said:

@Jamie Wilson How's your E1 doing now since the lithium upgrade?! 

I'm thinking about taking on this project.  Amazon has a 4pack LiTime 48V 120Ah (4-Pack 48V 30Ah) GC2  for $1,359.  

How do you go about doing an algorithm update for the original charger?  

Her at 19:58