Member Jonathan Kay Posted August 20, 2018 Member Share Posted August 20, 2018 Seems I have a parasitic discharge going on, that flattened the battery in that time. I think I've found the culprit ( self canceling indicator unit )...Drain at rest *varies enormously between different Sevens. How was that unit wired?ThanksJonathan* As we know due to revilla's research. Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted August 20, 2018 Member Share Posted August 20, 2018 As once as they go flat they're knackered. Is this generally true for the types of lithium batteries we're all considering for Sevens?ThanksJonathan Link to comment Share on other sites More sharing options...
7 wonders of the world Posted August 25, 2018 Share Posted August 25, 2018 no you can recover them, I posted how to in a previous thread............. which I cant bl00dyfind now..... Link to comment Share on other sites More sharing options...
ChrisC Posted August 25, 2018 Share Posted August 25, 2018 Lithium batteries are everywhere in our daily lives, most have protection to prevent damaging discharge level, like phone and laptop batteries, but the lightest of them all the lithium polymer or lipo used in radio controlled models has no discharge protection. They puff up and become very dangerous to charge if abused with discharge beyond the safe limit. I have see a few lipo fires and the aftermath of a lipo fire in a house, all not good. Just look on YouTube for lipo fires to see the type of damage a small battery can do. As for putting on in my car, well I would, providing it lion based and has protection circuits to prevent over or under charge, after all these batteries are the basis of EV cars at the moment. Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted September 10, 2019 Member Share Posted September 10, 2019 Any more experiences of lithium batteries in Sevens, please?ThanksJonathan Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted November 17, 2019 Member Share Posted November 17, 2019 Bounce...Jonathan Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted January 20, 2020 Member Share Posted January 20, 2020 Bounce... anyone?Jonathan Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted January 25, 2020 Member Share Posted January 25, 2020 The Powerlite PS-20 has been mentioned in a couple of threads.Powerlite's own page, including data sheets.20 Ah CC(A) 630A Mass 2.4 kgTheir price is £210 including a charger.Jonathan Link to comment Share on other sites More sharing options...
David_B Posted January 5, 2021 Share Posted January 5, 2021 Hi,No additional feedback about powerlite PS-20 ?thanks ! Link to comment Share on other sites More sharing options...
CycleSi Posted January 5, 2021 Share Posted January 5, 2021 I had (until recently) an Anti Gravity Li-Ion battery in my 7 and although it did the job just fine it suddenly started to swell up and not want to start the car as easily as it had always done before. The people who maintain my 7 also look after a lot of race cars/teams and they said they are increasingly seeing Li-Ion batteries catch fire so advised me to replace it asap.Upon their recommendation I fitted an Odyssey Gel battery and all is well again.I'm not saying I'm against Li-Ion batteries, but I agree with others who say some kind of circuit protection is vital. Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted January 5, 2021 Member Share Posted January 5, 2021 Thanks for that... there must be more experiences out there by now to add... ?JonathanPS: The Odyssey range aren't gel batteries, they're AGM: https://eu.odysseybattery.com/applications/automotive/ https://en.wikipedia.org/wiki/VRLA_battery Link to comment Share on other sites More sharing options...
CycleSi Posted January 5, 2021 Share Posted January 5, 2021 Of course, I didn't mean gel - sorry, I was thinking of something else.I went for their PC 625 model by the way as that was the perfect fit in my R300. Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted July 26, 2021 Member Share Posted July 26, 2021 Any more experiences to share, please?ThanksJonathan Link to comment Share on other sites More sharing options...
Roger Ford Posted July 26, 2021 Share Posted July 26, 2021 My JWM one has been great. Turns the engine over much better than my old Banner.More than once I've left the ignition and kill switch on and drained the battery. The battery management system just cuts it off at a pre-set voltage, so you just rig up the charger, give it 45 minutes charge and it's ready to go again.I wouldn't recommend buying one without the specific charger. Given that it charges from the alternator when in use, you'd think that it would be happy on any old charger, but I think there's a difference in the DC supplied from a car regulator/rectifier, and the type DC supplied by a normal charger, but I'm not clear on the difference. Link to comment Share on other sites More sharing options...
Mechanical Moz Posted July 26, 2021 Share Posted July 26, 2021 I managed to pick one of these up for a bargain £44 back in March https://www.amazon.co.uk/gp/product/B01GZCNIWI/ to replace a dead Banner. Thought I'd take a punt at that price, if it was no good for the 7 then it was destined for the mower.So far working just fine on my 1.8K, I have a battery isolator fitted and don't use a conditioner with it. Link to comment Share on other sites More sharing options...
David_Long Posted July 26, 2021 Share Posted July 26, 2021 #39Alternators are CCCV (Constant Current, Constant Voltage) in nature and what a Li-Ion battery requires. The dangerous type of charger is a CC (constant current) that ramp up the voltage to maintain the current. They were ideal for trickle charging lead acid, but are dangerous when used on Li-Ion.. Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted July 26, 2021 Member Share Posted July 26, 2021 The small smart "conditioning" chargers typically used with Sevens now often include a specific mode for lithium batteries. (As they do for AGM batteries.)Jonathan Link to comment Share on other sites More sharing options...
Roger Ford Posted July 26, 2021 Share Posted July 26, 2021 JK: Mine doesn't, sadly (CTEK 5000). Too old I guess.DL: that makes sense. Though it seems to me it would be a pretty dumb charger that ramps the voltage up beyond a safe level just because the battery doesn't want to take any more charge. Don't they have a ceiling voltage? My bench power supply has CV and CC modes, but there's always a limit on the current and voltage respectively. Basicallyt it'll work in CC mode until the voltage needed to supply that current reaches the preset voltage, then will switch over to CV mode.Edit: I guess the problem is simply that the ceiling is too high. If a charger wants to supply 5A, then it might decide that 17v is a reasonable level to fast-charge a lead-acid battery, but might be way too high for lithium. Link to comment Share on other sites More sharing options...
David_Long Posted July 26, 2021 Share Posted July 26, 2021 #43Old school constant current chargers where used as lead acid batteries don't take charge very efficiently. Some of the charging current ends up 'gassing' the electrolyte, so current is lost in the process. Once they are past 80% charge, they need extended period of charge to reach 100%. A typical car battery CC charger simply knows it is safe to 'overcharge' a lead acid battery by around 2 amps without any harm. That's not to say a CV charger will not work - the voltage required to deliver full charge is 14.4 volts, but generally it will consume some current at that voltage even when 100% charged. Li-Ion on the other hand are extremely efficient at storing charge. Charging has to stop when they reach full capacity. Continuing to charge beyond 100% will only generate heat that can lead to a runaway reaction. Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted January 23, 2022 Member Share Posted January 23, 2022 "JMT HJTX20H-FP Li-on for me hooked to a NOCO conditionerBattery weighs 1.4kgHandles a 13:1 CR Duratec with ease."Manufacturer claimed CCA: 420 A. Current price: £187 https://www.elitemotorcycleservices.co.uk/HJTX20H-FP-JMT-Lithium-ion-batteryJonathan Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted January 24, 2022 Member Share Posted January 24, 2022 There must be some more out there...Jonathan Link to comment Share on other sites More sharing options...
Roger Ford Posted January 24, 2022 Share Posted January 24, 2022 From the website of that JMT battery....*** IMPORTANT *** Although JMT lithium-ion batteries discharge at a slower rate than coventional batteries it is vital that they are not allowed to go completely flat.DO NOT buy that battery. If the warning is correct, it doesn't have a proper battery management system which cuts the connection when the voltage drops too low. I've left my ignition on a number of times with my Jack Webb Motorsport battery, and it just cuts off at something like 10.5v. You then connect the charger and the BMS reconnects the battery and it charges as normal. Without a BMS it would have killed it stone dead. Each time.I know some people don't like to deal with the Webbs but the product is very good.People get quick hung up on capacity. Capacity for a starter battery is almost irrelevant unless you're running electrics which exceed the output of your alternator. That's unlikely on a Caterham, unless you're trying to put a tent up using your headlights without the engine running, or something similar. The only thing that normally matters is the cranking current. Link to comment Share on other sites More sharing options...
Sooty Posted January 24, 2022 Share Posted January 24, 2022 I sell Lithium batteries for Golf Trolleys and the last 18 months has been a nightmare in the Li market as getting supplied out of China has been very challenging as most shippers have avoided shipping what are defined as dangerous goods. Powerlite were very active but have now pulled out of the market. Yes they are expensive but they do have a much longer life span of properly looked after. Good ones will have an internal battery management system pcb that stops the battery being overly charged or discharged.In terms of lifespan , and here I am quoting cyclic use data, a lead acid battery will have a design life of 200 cycles whereas the equivalent LiFePo4 battery can be expected to achieve 2000 cycles at roughly 4 times the cost. The mathematics is clear.Charging profiles are very different so you MUST use a lithium compliant charger on a lithium battery and NOT use a lead acid charger Link to comment Share on other sites More sharing options...
StevehS3 Posted January 25, 2022 Share Posted January 25, 2022 One thing I have wondered about with regard to charging is whether the alternator charges the Lithium battery correctly as that is designed for a lead acid battery. Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted January 25, 2022 Member Share Posted January 25, 2022 This hasn't come up as a problem with retrofits.I expect that it's because the integrated battery management system (see above) looks after the battery.But it is interesting that a different mode is needed for a smart conditioning charger when it isn't for an alternator...Jonathan Link to comment Share on other sites More sharing options...
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