LiFePO4 Batteries in Evolve GT?

And how far can you go after the board switched to eco mode. And are you riding all terrain or street wheels? Too me it sounds like a software issue and not a voltage sag issue. The battery would do fine but they restrict the performance by the software.

How can you do series then parallel?

By connecting two packs in series you increase the voltage, but keep the same mAh rating, so two 5s in series would be 10s.

Connecting another pair of 5s batteries in parallel, might be done to increase the total mAh of the pack, keeping the voltage the same.

All we have to do is reprogram the board to not be retarded. I wonder what would happen if you used a regular remote. Where exactly is the"Switch to Eco mode" command. The remote, ESC or BMS?

Not a software issue imo. Would you rather sag until the esc cuts off? Would you rather it sag under 2.5V/cell and damage the cells permanently? Cause thatā€™s what happens when you run them under 2.5V/cell. Iā€™ve ran a pack down to 2V/cell and it now holds roughly 80% capacity after a FOUR cycles.

2 Likes

Just a little explenation. The evolves battery % value shows the battery capacity for a no load situation. So i guess when it shows 0% then the battery should bet at roughly 3.5V a cell with no load. If you would add load in this Siutaion it would drop to 2.5V. Now as VigasG mentioned the board is at 50% in a no load situation. Now you add load and the % value drops below 20%. I bet money that we are not even below 3.0V under load in this situation. When you do this a bit too long the board switches automatically to ECO mode. And i would say they do this too early.

But why would they do this? first guess: Their motor controller is not really smart and the ECO mode switch is controlled by the remote. And if the software is bad the remote would not even know that the board is at a load situation with voltage sag and thinks the battery is that low in a no load situation. second guess: Could be that they want to be on the very safe side with their batterys and try to avoid service calls because of broken batterys. On a street setup you wonā€™t stress the batterys too much but on the All Terrain setup they can get warm. third guess: They tell that the board can do a lot of miles. And by reducing the power you can achieve a much better range. Otherwise the costumers would complain very soon that the board has a bad range.

Can you tell what brand and model of Li-ion is build in there? Maybe they can be replaced with some major-brand higher-quality li-ion cells that sag much less?

Batteries get damaged when under 2.5V, regardless of the loadā€¦ you can be running 25A through them or no load through them, if they go beneath 2.5V at ANY point, they get damaged.

I ran batteries under load to 2.0V, they sprung back to 2.8V at no load. They were still permanently damaged even though they were barely cycled. I would love to post the graphs but it is work related and I cannot do so.

You could test it yourself with a single cell and a programmable load. Try running your cells down several cycles and just watch the capacity go to crap.

The 3.0V sag limit might be conservative, but itā€™s a safety feature to keep your batteries from dying 6 months from now and claiming warranty or something because the battery is bad. You can say itā€™s too early, but it really isnā€™t if you want your batteries to last 100s of cycles.

So yes, guesses 2 and 3 are probably right.

2 Likes

Iā€™m riding on the street wheels. I havenā€™t really done an all-out range test. But based on how the board reacts and the battery percentage, I could easily get 22+ miles. If I was light and didnā€™t go up hills I could probably get fairly close to the 31 miles they advertise (28 Iā€™m guessing). Iā€™ve seen some people (not Evolve) get almost 37 miles on ECO so Iā€™m not all that worried about range.

No one quite knows what exact brand they are using but I can confirm they arenā€™t a brand name - which is awful considering this board is $2000+. They havenā€™t had any issues with quality but the voltage sag could be because they cheaped out on the cells. Iā€™m 100% sure the batteries arenā€™t manufactured by Samsung, LG or Panasonic.

@PXSS i think you got me wrong. Just to make it clear, what do you think at which load the cell is when the remote shows 50% without load.

I donā€™t know if Iā€™m getting your question. But if you are asking whether the 50% reading is accurate - Iā€™m assuming it is, since riding on ECO mode limits motor power and the sag is down 2% while accelerating and goes back up to 50%/ non-load percentage while cruising.

Iā€™m pretty sure 2 is correct. The cells arenā€™t of the highest quality so restricting them from sagging too much would stop them from dying. 3 might not be so accurate as they pretty clearly state everywhere that ECO mode will give you the most range and that the 31 mile estimate came from ECO mode etc. etc.

No the sentence was for PXSS. Because he thinks that i meant to put load on a cell which is already down to 2.5V even without load. But all of this doesnā€™t matter because we canā€™t change it anyway. Only if you would use VESCs you could control it. But you donā€™t have access to the evolve software.

How do you know, you canā€™t b 100% sure.

You want to fix the voltage sag, but youā€™ve to find out the exact battery specs first to see what causes the sag. Or you can replace random parts of the board and in the end nothing helps because the whole drive-drain is bad enginerred.

Whatā€™s wrong with the drive train?

Is there anything good about this board lol?

@Ackmaniac, no I got what you meant. When it is at 50%, no load voltage is ~3.6V. What I meant is if he puils enough current to sag them down to 2.5V, the battery gets damaged regardless of the no load voltage.

@VikasG. My recommendation is go to a LiPo setup. You can still add a BMS to LiPos. Theyā€™re no different than Li-ions in that regard. Pros: little/no sag, more power, cheap. Cons: lower energy density, needs a new bms and esc.

Iā€™ve done some research and kinda confirmed with Evolve that the batteries arenā€™t from any major brand. The only real specs I can give are that the the batteries are 10s4p 360Wh at 36V/10a.

Nothing is wrong with the drive train. He was just saying that hypothetically - as in if I spent all my money replacing parts but in the end the whole drive train was the issue, it wouldā€™ve been pointless.

1 Like

Honestly, thanks for the recommendation. But my only real concern with LiPos are the extensive care you have to take of them to prevent fire-hazards etc. I doubt the Carbon GT has a fire retardant casing like the Boosted Board since the entire casing is underneath your feet.