LiTime 230Ah batteries show weird voltage after charging

rh5555

I have purchased 2 of the newly released LiTime 230Ah lithium batteries for my upgrade from AGM and have discovered an interesting weirdness that others might find interesting.  Charging these batteries couldn't be simpler, just charge as fast as your converter will let you (up to 200A) until the battery voltage reaches 14.4V at which point the current drops off quite rapidly till the battery flips some kind of internal switch and doesn't accept any more charge.

What is weird is that once you've finished charging, the battery voltage reads low - around 12.8 to 13V. If you discharge the batteries at 5A or more for a minute or two, the battery voltage rises to the expected 13.3V (or more).  I have to guess that this is due to the LiTime battery management system (BMS) that has to switch over from "don't accept any more charge" mode to "normal operation" mode.

This behavior, though weird, doesn't really matter if you're using just one battery (other than the battery appearing, voltage-wise, to be almost dead right after charging), but if you have 2 or more in parallel then the overall behavior may get quite bizarre:  You'll charge both batteries up till they stop taking charge, then when the charger is no longer active, you start discharging.  If you separated the batteries at this point, one would show a higher voltage than the other (as they are both in "don't accept any more charge" mode), and that battery will preferentially discharge.  That will cause this battery to come out of "don't accept any more charge" mode and switch to "normal operation" mode, with a consequential increase in its battery voltage.  The other battery won't discharge at all until the first battery's voltage drops low enough, at which point current starts to flow from the second battery and it comes out of "don't accept any more charge" mode and switches to "normal operation" mode too.  Now the second battery will preferentially discharge till both batteries balance up.  This isn't a problem, but if you separated the batteries for some reason when partially discharged, they might show radically different voltages across their terminals.  Only downside that I can think of is that one battery may get way more exercise than the other, but as they each have 4000 discharge cycles available, it really doesn't matter.

I have no idea if this weird behavior is exhibited by other LiTime batteries, let alone other manufacturer's offerings (but I wouldn't be surprised...).

AnOldUR

Do you plan to do a full draw down after charging to confirm the amp hours available?

rh5555

AnOldUR said:

Do you plan to do a full draw down after charging to confirm the amp hours available?

That's on my to-do list.

elbolillo

my suspicion is that the LiTime BMS is not functioning properly.

manyman297

@rh5555 Let us know how those batteries perform. I’ve got my eye on the 230ah flavor to replace my AGMs this upcoming camping season.

otr_320

rh5555 said:

I have purchased 2 of the newly released LiTime 230Ah lithium batteries for my upgrade from AGM and have discovered an interesting weirdness that others might find interesting.  Charging these batteries couldn't be simpler, just charge as fast as your converter will let you (up to 200A) until the battery voltage reaches 14.4V at which point the current drops off quite rapidly till the battery flips some kind of internal switch and doesn't accept any more charge.

What is weird is that once you've finished charging, the battery voltage reads low - around 12.8 to 13V. If you discharge the batteries at 5A or more for a minute or two, the battery voltage rises to the expected 13.3V (or more).  I have to guess that this is due to the LiTime battery management system (BMS) that has to switch over from "don't accept any more charge" mode to "normal operation" mode.

This behavior, though weird, doesn't really matter if you're using just one battery (other than the battery appearing, voltage-wise, to be almost dead right after charging), but if you have 2 or more in parallel then the overall behavior may get quite bizarre:  You'll charge both batteries up till they stop taking charge, then when the charger is no longer active, you start discharging.  If you separated the batteries at this point, one would show a higher voltage than the other (as they are both in "don't accept any more charge" mode), and that battery will preferentially discharge.  That will cause this battery to come out of "don't accept any more charge" mode and switch to "normal operation" mode, with a consequential increase in its battery voltage.  The other battery won't discharge at all until the first battery's voltage drops low enough, at which point current starts to flow from the second battery and it comes out of "don't accept any more charge" mode and switches to "normal operation" mode too.  Now the second battery will preferentially discharge till both batteries balance up.  This isn't a problem, but if you separated the batteries for some reason when partially discharged, they might show radically different voltages across their terminals.  Only downside that I can think of is that one battery may get way more exercise than the other, but as they each have 4000 discharge cycles available, it really doesn't matter.

I have no idea if this weird behavior is exhibited by other LiTime batteries, let alone other manufacturer's offerings (but I wouldn't be surprised...).

@rh5555, this is *not* normal charging behavior for *any* 12v lifepo4 battery.  Your use of the word "weird" to describe how your battery is charging is appropriate.

As I tried to explain to you in a previous thread, a 12v lifepo4 battery should charge to its final charge voltage (in your case 14.4v) in a completely smooth, LINEAR fashion.  If it does not (charging stops abruptly before charge current reaches zero), this indicates the BMS activated a cell level high voltage disconnect.  This occurs when one cell exceeds ~3.650v (100% SOC) before the other 3 cells. This one cell prevents the 3 remaining cells from from being charged to 100% SOC---reducing the ah capacity of the battery.  Important to note, a 12v lifepo4 battery (with 4 cells in series) is only as strong as the weakest cell.

Another tell-tale sign that the cells in your battery are unbalanced are your comments about battery voltage after charging.  You mentioned reading 12.8 - 13.3v soon after charging was "complete".  Absolutely not normal.  If your battery was truly charging to 14.4v in a proper, normal, balanced fashion, battery voltage should remain above 14.0v for many hours.  It should take approx. 24-48 hours for the battery voltage to finally rest at 13.35 - 13.40v.  My comments assume zero loads and zero charge current after charging is complete (i.e., battery completely disconnected).

I would surmise the extreme weirdness you're experiencing with your batteries connected in parallel is being caused by unbalanced cells in one or both batteries, further aggravated by the two batteries themselves being unbalanced with each other.  Very hard to properly balance two batteries in parallel when the cells in the batteries themselves are unbalanced.  A worst case scenario.

I concur with @AnOldUR, you should do a load (ah capacity) test on each battery. An ah capacity or load test (after charging or attempting to charge to 100% SOC) will provide a general idea whether your batteries are performing satisfactorily or not.  In my opinion, every lifepo4 battery owner should do a load test after purchasing or building a lifepo4 battery to confirm the overall health of their battery---and to confirm that they actually received what they paid for. 

Good luck!

elbolillo

A quick search regarding LiTime batteries reveals a number of issues that users have had with these batteries not properly balancing...

rh5555

Some more information:

• I have 2 of these 230Ah LiTime batteries.  Both exhibit the weird behavior detailed above.
• Judging by some web surfing, I'm not alone: Lots of others see the same issue as detailed here
• I discharged one of my batteries down to 10V, and it delivered 220Ah
• These are the first batteries from LiTime that feature low temperature charge protection.  This prevents you from charging the battery below 0°C.

Quoting a reply from Litime to another owner who was inquiring about this behavior:

This is our new battery protection function, [Full Charge Protection Function].
This function provides more comprehensive protection for the battery and better performance of the battery system in two ways.

① Reduces voltage oscillations in the battery or system, maintains system performance and prevents abnormal system shutdown.
In situations where the battery needs to be connected to the charger for a long period of time, repeatedly turning on the battery after it has been fully charged can cause voltage oscillations in the battery or system (the battery voltage repeatedly cycles from resting down to charging up), which can affect system performance and even cause the system to shut down abnormally.

② Extend the life of the battery.
When a LiFePO4 battery is kept on high voltage charge for a long period (14.6V full charge voltage), its life span decreases relatively faster.
This function allows the battery to turn on the charge protection after a full charge, and then turn on the charge again after a certain discharge or resting voltage below a certain value, which can effectively circumvent the problems that may arise when the battery needs to be connected to the charger for a long time to charge without discharging.

After this battery is protected from overcharging,
the tested battery voltage (not the real voltage) will be lower than the real voltage.
To calculate the SOC (%), add 0.5V to 0.7V to the tested battery voltage.

We recommend that you take a small load (50W or above)and discharge it for 3-5 minute,
then leave it for 30 minutes before testing the voltage,
at which point the voltage should return to normal fully charged voltage(13.33V and above)

Here is some info about the BMS of the 12V 230Ah Plus battery for you：
Balance voltage for single cell：3.525±0.025V
Balance current for single cell：35±10mA
The balance module is working, it is recommended to charge with a small current, and the balancing time will be longer and more conducive to balancing.

Here are the recommended setting parameters for you：
Absorption Voltage：14.4V~14.6V
Float Voltage: 13.8V
Re-Bulk Voltage Offset: 13.0V
Tail Current：4.6A
Storage Voltage：50% SOC (see attached SOC form)
Bulk Time Limit： default
Re-bulk Current：default
Absorption Duration (Adaptive/Fixed)： Adaptive
Maximum Absorption Time (for Adaptive)/Absorption Time (for Fixed)：2h0m
Repeated Absorption：default
Others are default.

It would seem that since LiTime was developing a new BMS that could shut off charging when the temperature got too low, they decided to also implement a charge shut off when the battery is close to being fully charged.  It seems that this causes issues with some chargers, fortunately not with the Victron Multiplus II that I'm using.

One final behavior to be aware of:  When I discharged the 230Ah battery down to 10V, the BMS disconnected the battery from further discharge (showed no voltage across its terminals).  I was using the VE.Bus smart dongle to control my Victron charger, and as it gets its power from the battery, it didn't work and I couldn't turn the charger on.  Had to pull out my laptop and VE.BUS to USB dongle (that is powered from my laptop) to get the system up and running again.

otr_320

rh5555 said:

• I discharged one of my batteries down to 10V, and it delivered 220Ah
  

@rh5555, if you're happy with 220ah from a 230ah battery that's all that matters.  Me, I wouldn't be. You're running an ah deficit right out the gate.  Ah capacity/cycle life only goes down---it never gets better.  You're deficit tends to confirm my suspicion you have unbalanced cells.  Curious, what current did you use for your load test? If you based it on day-to-day ah consumption that is *not* a valid load test.

In contrast, we get 305ah from a 304ah lifepo4 battery discharging down to 11.0v at a continuous .33c (101a).  If we discharged to 10v (not recommended) we'd get a tad more ah's.  We'd get even more ah's if we discharged at a lower current, say .1c (30a).  

Bottom line, lot of variables at play when doing a load-test.

otr_320

elbolillo said:

A quick search regarding LiTime batteries reveals a number of issues that users have had with these batteries not properly balancing...

Sad to say, unbalanced cells are a common problem with many 12v lifepo4 batteries that use 4 prismatic cells in series.  With this cell configuration the battery is only as strong as its weakest cell.  Nearly all the 12v lifepo4 batteries sold on Amazon use this 4s configuration. Some top-tier manufacturers also use prismatic cells.  However, due to their premium pricing they're much more likely to take the time and money to ensure the cells are properly "matched" before production---something budget lifepo4 battery manufacturers are unwilling to do for cost reasons.

If I was in the market to purchase a budget lifepo4 battery (or cells), I would only purchase from a source that offers a no-questions asked return policy.  I would load-test the battery several times before the return window closes.  It it fails to produce its rated ah capacity during any test, immediately return it.  Assume the warranty is worthless---most generally are.

For those who'd rather not take a chance on in-series prismatic cells, they may want to take a closer look at the 12v 100ah Battleborn battery.  Yes, I agree BB batteries are somewhat overpriced.  However, there's a reason they cost more that goes beyond the BB name.  The BB 12v 100ah lifepo4 battery uses 100+ cylindrical lifepo4 cells in a parallel/series arrangement.  This cell arrangement costs more to produce, but it presents a distinct advantage vs. 4 prismatic cells in-series in terms of increased redundancy.  In the event a few cells become weak or unbalanced it has much less effect on the overall ah output of the battery.  The same cannot be said for 4 prismatic cells in series.

rh5555

My load test was very crude.  Just using the Victron MP2 assessment of current draw sampled every 10 minutes or so.  To do a better measurement, I'll have to pull my BMV-712 out of the trailer and wire it in.  Maybe tomorrow...

otr_320

rh5555 said: When I discharged the 230Ah battery down to 10V, the BMS disconnected the battery from further discharge (showed no voltage across its terminals).  I was using the VE.Bus smart dongle to control my Victron charger, and as it gets its power from the battery, it didn't work and I couldn't turn the charger on.  Had to pull out my laptop and VE.BUS to USB dongle (that is powered from my laptop) to get the system up and running again.

When you ran your test is there any particular reason you didn't simply remove shorepower with the Multiplus charger (and inverter) left in the ON state? That way when the battery implements low voltage disconnect all you have to do is apply shorepower.  When shorepower is applied the charger automatically turns on and supplies 12v power to the camper (and the VE dongle).  No need to drag out the USB dongle and laptop.

elbolillo

@otr_320 @rh5555 It's fascinating following this thread and your insights. I have learned much about batteries and charging since purchasing our Tab 320 and now Tab 400. I installed 4 100ah BB in our '23 Tab 400 along with a Victron Multiplus 3000w inverter. I was able to purchase the batteries when BB had sales running so that definitely helped with the total cost of purchase. I didn't do exhaustive research on LiFePo4 batteries, but the investigation that I did kept pointing me back to brands like Battleborn. My experience has been very positive. I have consulted with BB technicians to verify my installation and they have always been quick to respond.

I am geeky enough to like to play around with these things on my Tab, however, at the end of the day, I just want to get out and not have to worry about my batteries. We recently took a 13 day trip to Big Bend NP and during that time the lowest the battery bank went down was to 63%. With abundant sunshine and the rooftop solar and a 220w external panel I was able to keep everything running like a champ. This included heavy inverter usage to power our Starlink and keep our electronics charged. To me the peace of mind that comes with this setup is worth the extra cost.

rh5555

When you ran your test is there any particular reason you didn't simply remove shorepower with the Multiplus charger (and inverter) left in the ON state?

With 20-20 hindsight, this is what I should have done.  My point remains, though:  If your phone is your only method of connecting and you use it to set the Victron Multiplus II to "Inverter Only" and and then run your battery down to its low voltage disconnect, you have no simple way of recovering from this situation.

otr_320

elbolillo said:

@otr_320 @rh5555 It's fascinating following this thread and your insights. I have learned much about batteries and charging since purchasing our Tab 320 and now Tab 400. I installed 4 100ah BB in our '23 Tab 400 along with a Victron Multiplus 3000w inverter. I was able to purchase the batteries when BB had sales running so that definitely helped with the total cost of purchase. I didn't do exhaustive research on LiFePo4 batteries, but the investigation that I did kept pointing me back to brands like Battleborn. My experience has been very positive. I have consulted with BB technicians to verify my installation and they have always been quick to respond.

I am geeky enough to like to play around with these things on my Tab, however, at the end of the day, I just want to get out and not have to worry about my batteries. We recently took a 13 day trip to Big Bend NP and during that time the lowest the battery bank went down was to 63%. With abundant sunshine and the rooftop solar and a 220w external panel I was able to keep everything running like a champ. This included heavy inverter usage to power our Starlink and keep our electronics charged. To me the peace of mind that comes with this setup is worth the extra cost.

Thanks, @elbolillo!

Can't go wrong with Battleborn--especially 4 of 'em!  Paired with your Victron Multiplus 3000, you couldn't ask for better components.  

Your trip to Big Bend sounded awesome!  That's on our bucket list of places to visit.  Agree, it's a great feeling to be self-sustaining in a dry-camping environment--especially when you're able to pull it off with solar alone like you did.  Icing on the cake when your system performs so well you almost forget it's there. 

We just finished our annual 3 week camping trip to the FL Keys.  Unfortunately, only dry camping was available with 11p-7a quiet hours.  My wife really wanted access to a/c---24/7.  Our DIY 304ah lifepo4 battery pack (slightly larger than one Battleborn battery) and Victron Multiplus II 3000 stepped-up in a big way.  Together they powered our Air8 a/c throughout quiet hours with plenty of ah's to spare.  During the day, the Multiplus II's power assist/share mode and charger (with its superb power factor!!) allowed us to dial in the perfect load for our little Honda 2200 so it could power the a/c and charge our battery at the same time.

Technology, when it performs well, is the cat's meow!

rh5555

Going off-topic a bit here (while I do another discharge test (through my BMV, this time))...

@elbolillo and @otr_320, have you ever tried hooking your Victron Multiplus II units to a GFCI-protected outlet? Mine will often trip a GFCI.  I've tracked this down to about 2mA of ground current produced by the Victron added to about 3mA of stray leakage from other outlets in the trailer. I hope the latter will go down when we dry out come spring-time.  The Victron's ground current is apparently "normal" and I cannot do anything about it.

elbolillo

rh5555 said:

Going off-topic a bit here (while I do another discharge test (through my BMV, this time))...

@elbolillo and @otr_320, have you ever tried hooking your Victron Multiplus II units to a GFCI-protected outlet? Mine will often trip a GFCI.  I've tracked this down to about 2mA of ground current produced by the Victron added to about 3mA of stray leakage from other outlets in the trailer. I hope the latter will go down when we dry out come spring-time.  The Victron's ground current is apparently "normal" and I cannot do anything about it.

I have the Multiplus, not the Multiplus II. I have seen a number of complaints regarding the Multiplus II tripping. I can't recall what the remedy was.

otr_320

rh5555 said:

Going off-topic a bit here (while I do another discharge test (through my BMV, this time))...

@elbolillo and @otr_320, have you ever tried hooking your Victron Multiplus II units to a GFCI-protected outlet? Mine will often trip a GFCI.  I've tracked this down to about 2mA of ground current produced by the Victron added to about 3mA of stray leakage from other outlets in the trailer. I hope the latter will go down when we dry out come spring-time.  The Victron's ground current is apparently "normal" and I cannot do anything about it.

You started a thread about this same Victron Multiplus II 3000 GFCI issue back in Nov '23.  I was under the impression you rectified the problem.

In any event, both @elbolillo and I replied to your Nov '23 inquiry:

https://tab-rv.vanillacommunity.com/discussion/17907/gfci-question-for-owners-with-multiplus-ii-3000w-inverter-charger

rh5555

I ended up getting a replacement Multiplus II.  This one has a lower leakage current, though still not zero.

I also repeated the discharge test on one of my LiTime batteries:  Got 229.3Ah out of a 230Ah rated battery, discharging at 70 Amps.  Not complaining...  Tomorrow I'll test the other one.

otr_320

rh5555 said:

I also repeated the discharge test on one of my LiTime batteries:  Got 229.3Ah out of a 230Ah rated battery, discharging at 70 Amps.  Not complaining...  Tomorrow I'll test the other one.

Agree, not much to complain about.  70a is a .3c load.  Standard load tests usually call for .2c.  Your ah's would bump even higher at .2c.

Which battery did you test?  The "good" one or the battery with the strange/weird voltage readings?

rh5555

2nd battery came in at 228.4Ah.  Both batteries exhibited weird voltage readings at one time or another.

I suspect I might get somewhat higher Ah output if I charged the batteries sufficiently slowly.  LiTime says they only have 35mA of balancing current, so when charging at 120A that won't correct much of an imbalance.  When topping up with solar panels at a few Amps, the batteries would stand a better chance of getting fully balanced.

In conclusion, the LiTime 230Ah batteries seem to be a pretty good choice in the bargain Lithium market.

Pros:

• Built-in low temperature charging shutoff.  Most bargain lithium batteries do not have this.
• They are really compact.  The 230Ah battery measures 19"(L) x 6.7"(W) x 9.5"(H) and we all know space is at a premium
• The price is right
  

Cons:

• You cannot reliably use battery voltage as an indicator of state of charge.  
• I cannot recommend using these batteries in parallel (or in series, for that matter) because the BMS is likely to cause significant imbalance between batteries during discharge.
  

otr_320

rh5555 said:

2nd battery came in at 228.4Ah.  Both batteries exhibited weird voltage readings at one time or another.

rh5555 said:

• I cannot recommend using these batteries in parallel (or in series, for that matter) because the BMS is likely to cause significant imbalance between batteries during discharge.

@rh5555, 228.4 is not bad considering.

Based on your load tests, hard to make any sense of the various voltage readings you've mentioned throughout this thread and a previous thread.  I've monitored hundreds of lifepo4 charge/discharge cycles (most at cell level) over the last few years (using both DIY and off-the-shelf lifepo4 batteries).  With very little variation, they all exhibited the same charging behavior when charged at the same C rate and voltage.  Never seen a lifepo4 battery produce anywhere close to their ah rating when they exhibited a post-charge battery voltage as low as what you mentioned.

Have to say, that's a pretty serious con when you can't recommend connecting the LiTime batteries in parallel.  How did you balance the two batteries before connecting them in parallel?

In any event, glad both batteries tested as well as they did.  You seem to be experiencing a number of irregularities with your system.  Has to be frustrating.  Hopefully you'll get everything resolved soon.

schwartzki

I have the LiTime 230aH battery and post full charge they correctly sit around 13.8V. I have seen 1 time the odd lower voltage reading but it corrected itself within the hour and I thought the smart shunt was incorrect.

otr_320

schwartzki said:

I have the LiTime 230aH battery and post full charge they correctly sit around 13.8V. I have seen 1 time the odd lower voltage reading but it corrected itself within the hour and I thought the smart shunt was incorrect.

Interesting.  Do you happen to have the voltage/current trend data from your smart shunt for one of your charge cycles as the charge current transitions from, say, 10a to zero (or near zero) current? 

rh5555

My solution to the potential battery imbalance issue was to install a battery selector switch 

rather than a simple battery isolation switch.  This lets me observe the 2 battery voltages independently and, if necessary, discharge one battery preferentially to get it out of its "weird" mode.

As I detailed in my original post, paralleling these batteries may lead to some weird behavior, but you probably would never realize it was happening, and it doesn't really matter if it does happen.  However, the perfectionist in me doesn't find such behavior pleasing...

I also wanted to alert other users (like @schwartzki) that you may see a low battery voltage when you've just recharged your battery, and not to worry about it.

otr_320

rh5555 said: . . . discovered an interesting weirdness that others might find interesting

. . . What is weird is that once you've finished charging, the battery voltage reads low - around 12.8 to 13V . . .

. . . if you have 2 or more in parallel then the overall behavior may get quite bizarre . . .

. . . I have no idea if this weird behavior is exhibited by other LiTime batteries . . .

. . . discharge one battery . . to get it out of its "weird" mode . . .

. . . Both [batteries] exhibit the weird behavior . . . 

. . . paralleling these batteries may lead to some weird behavior . . .

. . . I cannot recommend using these batteries in parallel . . . 

. . . the perfectionist in me doesn't find such behavior pleasing . . .

. . . wanted to alert other users (like @schwartzki) that you may see a low battery voltage when you've just recharged your battery, and not to worry about it . . .

With all due respect, @rh5555, if I were in your shoes, the perfectionist side of me would want to know:

1) Why my lifepo4 batteries do not charge using the same charge profile as other lifepo4 batteries, and

2) Why my lifepo4 batteries do not function properly when connected in parallel.

"Not to worry about it" doesn't answer question #1.

A battery selector switch doesn't answer question #2.

Your constant, on-going use of "weird" to describe how your batteries operate is very, very telling. The above comments don't paint a rosy picture. 

A key question for you is whether you're willing to settle for weird.

rh5555

To answer your first question, @otr_320, these LiFePo4 batteries do charge just the same way as all other LiFePo4 batteries.  They accept a constant current up to 200A as the cell voltage steadily increases.  When the battery voltage rises above about 14.1 Volts, the charge current drops to zero over about a 90 second period as the battery voltage rises to the charging voltage of 14.6V.

    

Correct me if I am wrong, but isn't this rather fast?

It seems to me that what is different is that these batteries have a novel BMS.  It seemed weird initially, but now I believe that it is just a new and different way of managing batteries.  It seems that these are, maybe, 450Ah batteries and LiTime restricts the full charge (as well as full discharge) in order to extend the battery life.  That explains why they charge so fast:  Almost all the charge cycle is done in Bulk mode, once they enter absorption mode, the BMS relatively quickly shuts down further charging.  This charging shut down has an unfortunate consequence in that the batteries do not show their full voltage until you discharge them a bit and disable the full-charge detection.

I think the 3rd paragraph of my original post explains why the batteries might function in a previously-unexpected manner when paralleled.

I no longer consider the operation of these batteries weird, now that I think I understand them.  Let's start calling the behavior novel.

Hammick

When charging LifeP04 cells that don't have a BMS Will Prowse suggest putting the batteries in parallel and charging close to 100% using an adjustable power supply.  That's what I did with my 16 Lischen cells to get them balanced before connecting to my Orion Jr.2 BMS and hooking them to my inverter and CCs.

I'm wondering if that would be a benefit with LifeP04 cells that have a BMS.  I'm guessing probably not since there is no way to disable the balancing function.  Without a BMS the lower cells get balanced from the higher cells.  This took many days to complete with my power supply.

I am thinking of purchasing two of the 230ah Litime batteries and will set my bulk and float voltage to 54.4v when using the trailer (my understanding is balancing is not very effective until voltage is at 3.4 VPC.  I'll set the voltages lower when not using the trailer to extend their life