[Hybrid ReVolt]

While not the holy grail of a drop in Lithium IMA battery, I now have a drop in replacement for the 12V lead acid battery using LiFePO4 cells. Details are below. Feel free to ask any questions or let me know if you would like to reserve one. Initial price is $439 which includes US shipping.

Specs:
4 year warranty
4x LiFePO4 cells with custom BMS with low voltage cut-off and cell balancing
40Ah capacity @ 5 hour discharge test
11 lbs, 190mm x 121mm x 205mm

 

[Honda hybrid442]

Question only, don’t blast me for asking anybody. This is a 12 volt replacement battery with 4 year warranty with a average price of 110 bucks for each year, can you explained the benefits of having this and is this geared to the lto conversion cars.

 

[Saxjonz]

The battery is lighter???? They can be finicky with fluctuations. What else? I think not a good bang for the buck. For a bike they are great. I’ve had same battery going on ten years now. Never have to take it out in winter, great cranking power. How it’s better in a car? If money is no issue then I’d buy one because 7 pounds equals 1hp freed up so two extra ponies?


Sent from my iPhone using Tapatalk

 

[Honda hybrid442]

Thanks for your opinion. I'd like to hear hybrid revolts response since he does say ask any questions .

 

[Hybrid ReVolt]

The warranty is 4 years full replacement. You'll have a hard time finding that with lead as most are 1 to 3 years. Here in AZ where most non-hybrid cars only get about 2 years out of a lead 12V, I have a LiFePO4 a little over 4 years old in a family members Ford F150 and its still going strong (that truck would eat up batteries every 18 months to 2 years). The thought would be that under light use these batteries should last a very long time. This new battery would have benefits for any Insight - stock OEM, bypassed IMA, and even for those who don't drive often or have high 12V loads.

As for the battery being light weight causing an issue, that is completely not true. LiFePO4 batteries have much lower IR (internal resistance) and have a similar AH capacity to stock, so those with a large 12V load (AC inverter or large amplifier) would see a big benefit. These are rated at 40AH under a 5 hour test while most type 51 batteries are in the upper 30's at a 24 hour test - but lets just call the nameplate capacity the same. A lead battery really shouldn't be taken below 50% charge and cycling to 50% DOD a lead battery wont last very long, so you really only use a few AH before you start to shorten a lead batteries life. These LiFePO4 batteries will perform more like a deep cycle battery. They are rated at 3000 cycles at 50% DOD and taking one until the low voltage cutoff wont kill it - just charge it back it - they protect themselves from over discharge. Also, unlike a lead battery that you charge at 14.4V and draw from starting around 12.8V, these batteries let you start drawing from them within a few tenths of a volt - charge it to 14.4V and it will provide 100 amp at 14.0V (much better charge/discharge efficiency).

From my experiences in having one in my Insight, which is fairly stock, I've noticed the DC-DC doesn't stay on as long and has longer periods in between charging. This is likely due to not needing to "float" charge the lead battery and the fact that the LiFePO4 has better cycle efficiency. This takes a load off the engine which should help increase mileage. As to how much, I haven't been able to test just yet as temps have been on the rise here resulting in more A/C use.

For those who bypass their IMA battery and don't have the 12V being charged when at idle, the better charge efficiency and higher cycle life will really make this battery shine. You wont need to worry as much about draining your 12V in stop and go traffic. The battery will top up quicker when the DC-DC is on, and provide power longer when its off - all while not being damaged as much from such abuse (cycle life really helps here).

If you frequently park the car, while its not good for the IMA battery, LiFePO4 batteries are good for 6 months or longer without the need to top them up. Much lower self discharge. Just make sure you disconnect the 12v battery so the car doesn't run it down - you should be doing that anyway for storage.

So, there you have it. Better charge efficiency, better cycle life, better warranty. Yes, that comes at a price premium, but I feel its worth it in the long run.

 

[Honda hybrid442]

Thank you for a well informed anser . Good luck in your sales of the 12 volt battery .Sounds like a great product for some.

 

[Bull Dog]

Does the BMS you are using have a low temperature cutoff? I ask because charging LiFePO4 chemistry batteries at temperatures below freezing can result in permanent damage to the cells.

 

[Hybrid ReVolt]

Deal time! I have a small amount of these 12V LiFEPO4 batteries available at a deeply discounted price. These were warranty batteries that were returned due to a mis-configured BMS, and thus the Tesla cars had almost immediate issues. Basically they were manufactured with a "normal" BMS, not the Tesla specific one required. Original capacity was 30 or 40 AH depending on the model (5 hour test). We did a full test at 35 amp discharge from full to 10v and all are within 5ah of rated capacity. Some reduction in capacity is expected due to the higher current test we performed. Some have post terminals while others have screw types. These have no manufacturer warranty but I will offer a 30 day warranty. Good for most hybrids - Insight, Civic, Prius, etc, you just may need to adapt the terminals.

$100 each, which will include US ground shipping. Overseas, Hawaii and Alaska will have additional shipping charges.

 

[minor4326]

This battery seems good for Arizona. But what about Minnesota during winter? Please answer @Bull Dog question above.

 

[Hybrid ReVolt]

The BMS in these handle battery temperatures between -20C to +65C. They are not heated but the BMS is supposed to limit charge rate at low temperature.

These batteries are used in EV and hybrid cars all over the US. If something wasn't right I would have heard of it by now.

 

[Balto]

Deal time! I have a small amount of these 12V LiFEPO4 batteries available at a deeply discounted price. These were warranty batteries that were returned due to a mis-configured BMS, and thus the Tesla cars had almost immediate issues. Basically they were manufactured with a "normal" BMS, not the Tesla specific one required. Original capacity was 30 or 40 AH depending on the model (5 hour test). We did a full test at 35 amp discharge from full to 10v and all are within 5ah of rated capacity. Some reduction in capacity is expected due to the higher current test we performed. Some have post terminals while others have screw types. These have no manufacturer warranty but I will offer a 30 day warranty. Good for most hybrids - Insight, Civic, Prius, etc, you just may need to adapt the terminals.

$100 each, which will include US ground shipping. Overseas, Hawaii and Alaska will have additional shipping charges.

PM sent.

 

[Hybrid ReVolt]

Link to order:

12V LiFEPO4 order page

 

[Hybrid ReVolt]

Getting low on supply, so anyone needing one of these 12v batteries should act soon. There likely won't be any more at this price.

Also I have several failed batteries available, some apart others not, plus many loose LiFePO4 cells. The failed 12v packs usually have several good cells inside. Let me know if there is any interest in these.

 

[atikovi]

Hey Matt, any plans in the works for a drop in Li battery kit?

 

[*sean*]

@Hybrid ReVolt I put in an order for two, one for each Insight, but with a note to cancel the order if they don't have an automatic disconnect if someone leaves the dome or headlights on, or if the discharge current rating is not sufficient for an Gen 1 Insight starter motor to turn over a cold engine (I don't know the current draw of the Insight starter motor when cold, does anyone?)

It would be useful to know the max allowed charging voltage to keep the cells from being overcharged or one from running away (I'm pretty sure I can mod set the DCDC converter output to whatever is necessary, and it certainly can be disconnected with an external monitor to prevent exceeding the max allowed battery voltage) and it would be nice to know the cut-off low voltage as well. It does not look like there is a status output that we can leverage for an internal battery meter, but if there is one accessible inside the pack, I would be happy to look into it, assuming it can be disassembled. And of course, with the high and low voltage limits known it is easy to make a custom meter from one of the many Arduino-compatible boards that also have displays.

Thanks a TON for keeping us in mind and offering these to us, and reminding us that you still have them. I held off on these when you first announced them, thinking I could repurpose an LTO pack for this, but if these have the low voltage protection and can supply the max starting current, $100 is a terrific deal.

 

[Balto]

@Hybrid ReVolt I put in an order for two, one for each Insight, but with a note to cancel the order if they don't have an automatic disconnect if someone leaves the dome or headlights on, or if the discharge current rating is not sufficient for an Gen 1 Insight starter motor to turn over a cold engine (I don't know the current draw of the Insight starter motor when cold, does anyone?)

It would be useful to know the max allowed charging voltage to keep the cells from being overcharged or one from running away (I'm pretty sure I can mod set the DCDC converter output to whatever is necessary, and it certainly can be disconnected with an external monitor to prevent exceeding the max allowed battery voltage) and it would be nice to know the cut-off low voltage as well. It does not look like there is a status output that we can leverage for an internal battery meter, but if there is one accessible inside the pack, I would be happy to look into it, assuming it can be disassembled. And of course, with the high and low voltage limits known it is easy to make a custom meter from one of the many Arduino-compatible boards that also have displays.

Thanks a TON for keeping us in mind and offering these to us, and reminding us that you still have them. I held off on these when you first announced them, thinking I could repurpose an LTO pack for this, but if these have the low voltage protection and can supply the max starting current, $100 is a terrific deal.

Mine starts my 2L SR20DET engine just fine 🤷‍♂️ 🤷‍♂️ 🤷‍♂️ 🤷‍♂️ 🤷‍♂️

 

[Natalya]

Hi, I just ordered one of these.

I've done mudder's common "cut the white/green wire on back of DC/DC to keep 12V battery charged" mod on my Insight. this means the car is always charging the 12V while the car is on.

Should I reconnect that wire, or is it safe to leave the wire cut?

 

[*sean*]

@Natalya there may need to be a characterization session once we receive these, as in, baseline the capacity for each pack, find an appropriate charging voltage that balances pack lifetime with capacity; find out what the low voltage cutoff is and where that sits with respect to the cells inside, see what else we can learn about them. Matt wrote me that they do have a low voltage cutoff. Maybe see if we can expose per-cell info? lol

It might actually be reasonable to consider restoring the wire mod if one is not concerned about having max capacity for listening to the radio with the engine off or a possible reduction in life. It appears these hold another 1/3 kW. I'm not sure we know if Honda turned off the DCDC to extend IMA capacity or improve fuel economy?