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Laptop battery
I bought a battery for my HP G60 laptop.
It must be a poor quality battery cuz it only lasts an hour at most. If I buy a battery, is there a way I can be sure that it holds a full charge ? Thanks, Andy |
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Laptop battery
On Tue, 28 Nov 2017 13:37:58 -0800, mike wrote:
On 11/28/2017 11:34 AM, Andy wrote: I bought a battery for my HP G60 laptop. It must be a poor quality battery cuz it only lasts an hour at most. If I buy a battery, is there a way I can be sure that it holds a full charge ? Thanks, Andy Test it. No, you can't tell by asking the seller. What's the battery life claimed by HP? Depending on what you're doing, an hour may be good performance. Problem with a battery for an old computer is that most any brand name battery you find has been sitting in a container in Arizona for a decade. It's toast. The vendor probably made any new ones since two years after introduction. If you buy it from China on EBAY, it was probably made by cutting up old batteries that were stored for a decade in China and putting them into a new-looking battery case. Or maybe used batteries. Or maybe sub-quality cheapo cells. You might be able to have the pack refurbished with quality cells, but you won't like the price. Low price is a good indicator of a weak battery. High price is no guarantee that you won't get a weak battery. I bought a new battery for my Lenovo T43 on ebay. When I got it, it would not even take a charge. I left it charging for 2 days and still nothing. I complained to the seller. He sent me another one. That one worked great. I've been using it for a year now and still works great. It holds a charge for 2.5 to 3 hours. The old battery that came with the computer was so weak it woulod only hold a charge for a half hour at most. I find the same with cordless tools. When I bought a cordless drill, the batteries would last several hours for intermittent use, or about 45 min for continuous use. Three years later, I have to recharge them every hour and they wont last more than 10 min on continuous use. Even my car battery is dying. I have to make sure not to leave my lights on when I leave te car, or it wont start after 15 min. I used to be able to leave the lights on for hours.... Batteries are all meant to die. That is inevitable. Some last longer than others though. I guess it depends on how much you pay for them. The costly ones were made better (usually). I'm still waiting for someone to make some liquid that you pour in the battery to bring it back to life. I'll probably wait for this for eternity..... |
#3
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Laptop battery
On 11/28/2017 11:34 AM, Andy wrote:
I bought a battery for my HP G60 laptop. It must be a poor quality battery cuz it only lasts an hour at most. If I buy a battery, is there a way I can be sure that it holds a full charge ? Thanks, Andy Test it. No, you can't tell by asking the seller. What's the battery life claimed by HP? Depending on what you're doing, an hour may be good performance. Problem with a battery for an old computer is that most any brand name battery you find has been sitting in a container in Arizona for a decade. It's toast. The vendor probably made any new ones since two years after introduction. If you buy it from China on EBAY, it was probably made by cutting up old batteries that were stored for a decade in China and putting them into a new-looking battery case. Or maybe used batteries. Or maybe sub-quality cheapo cells. You might be able to have the pack refurbished with quality cells, but you won't like the price. Low price is a good indicator of a weak battery. High price is no guarantee that you won't get a weak battery. |
#4
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Laptop battery
Andy wrote:
I bought a battery for my HP G60 laptop. It must be a poor quality battery cuz it only lasts an hour at most. If I buy a battery, is there a way I can be sure that it holds a full charge ? Thanks, Andy I can give you a basic inventory on what is in a battery system. I don't know all the details well enough, to provide the exact right diagnosis. ******* The battery consists of: 1) Multiple LiCo cells, with welded conductors between cells. The cells have protection features, like each cell has an internal fuse, to prevent accidents. If a battery pack goes "open circuit", a protection feature may have tripped to prevent a fire. It can never work after that. 2) The battery has a PCB with a small "fuel gauge" chip on it. This communicates over a serial bus, to the laptop. The "fuel gauge" chips, there are many brands, and the right chip must be in there for the laptop to work with it. The fuel gauge keeps track of "charge cycle count", as well as a "capacity loss parameter", so that the laptop can figure out the reduction in capacity with time, and be in a better condition to detect when it's time to hibernate the computer (before the battery drops below 0%). If the battery loses 0.1% of its life on each full recharge, and the gauge logs 100 charge cycles, then the battery has lost about 10% of absolute capacity. The fuel gauge includes a number of registers, with information like that stored inside. It must be properly programmed at the factory, to represent the behavior of the cells well. 3) The plastic casing on the battery has eight contacts. Two for VCC. Two for GND. At least one contact of the remainder is used for the serial bus. Some packs also have an ENABLE pin, and that prevents energy from appearing on VCC and GND, unless the battery pack is seated in the bay. So if you drop your screwdriver across the power blades while the pack sits on your desk... it might not catch fire :-) The ENABLE pin inside the laptop, would ground the pin and signal the pack is now inside a laptop, so it's safe for VCC and GND to connect to the actual battery cells. 4) The laptop itself has an autonomous charge management subsystem. Even if the CPU isn't running, some kind of chip in there charges the battery, and stops charging before the battery is overfilled in a dangerous way. A battery may not be properly charged, due to a failure in that subsystem, or a failure of the power adapter. ******* It could be that the charging process is stopping after the CC phase. That would leave you with 65% fuel (second graph). Maybe it takes less time than normal, to fill to 65%. And then less time than normal, to empty it. http://batteryuniversity.com/learn/a..._ion_batteries I can't say much more than that. A battery bought from HP, probably works correctly. Batteries should always be bought from "high volume" sellers. A battery sitting on the shelf in a "mom and pop" computer store, could already be ruined by aging. You want "freshly constructed" laptop batteries for best results. A ten year old battery, may not take a lot of charge cycles due to age. I suspect a disagreement between (2) and (4), and the pack might not be properly designed for G60. The aftermarket suppliers try their best, when making this stuff. They probably weren't trying to save money, by cutting corners. Savvy buyers, use the reviews from previous customers, to get some idea whether the packs are "good". If the supplier is a middle-man and not a manufacturer, then there can be lot-to-lot variation. Like, if the middle-man buys from Larry one day ("good" pack) and from Moe the next day ("bad" pack), then even sellers with reviews may not be enough. If the batteries were nickel cadmium, like many years ago, there wouldn't be all these features. Batteries are this complicated, because of the risk of fire with this particular battery chemistry. Paul |
#5
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Laptop battery
On Tuesday, November 28, 2017 at 3:54:51 PM UTC-6, Paul wrote:
Andy wrote: I bought a battery for my HP G60 laptop. It must be a poor quality battery cuz it only lasts an hour at most. If I buy a battery, is there a way I can be sure that it holds a full charge ? Thanks, Andy I can give you a basic inventory on what is in a battery system. I don't know all the details well enough, to provide the exact right diagnosis. ******* The battery consists of: 1) Multiple LiCo cells, with welded conductors between cells. The cells have protection features, like each cell has an internal fuse, to prevent accidents. If a battery pack goes "open circuit", a protection feature may have tripped to prevent a fire. It can never work after that. 2) The battery has a PCB with a small "fuel gauge" chip on it. This communicates over a serial bus, to the laptop. The "fuel gauge" chips, there are many brands, and the right chip must be in there for the laptop to work with it. The fuel gauge keeps track of "charge cycle count", as well as a "capacity loss parameter", so that the laptop can figure out the reduction in capacity with time, and be in a better condition to detect when it's time to hibernate the computer (before the battery drops below 0%). If the battery loses 0.1% of its life on each full recharge, and the gauge logs 100 charge cycles, then the battery has lost about 10% of absolute capacity. The fuel gauge includes a number of registers, with information like that stored inside. It must be properly programmed at the factory, to represent the behavior of the cells well. 3) The plastic casing on the battery has eight contacts. Two for VCC. Two for GND. At least one contact of the remainder is used for the serial bus. Some packs also have an ENABLE pin, and that prevents energy from appearing on VCC and GND, unless the battery pack is seated in the bay. So if you drop your screwdriver across the power blades while the pack sits on your desk... it might not catch fire :-) The ENABLE pin inside the laptop, would ground the pin and signal the pack is now inside a laptop, so it's safe for VCC and GND to connect to the actual battery cells. 4) The laptop itself has an autonomous charge management subsystem. Even if the CPU isn't running, some kind of chip in there charges the battery, and stops charging before the battery is overfilled in a dangerous way. A battery may not be properly charged, due to a failure in that subsystem, or a failure of the power adapter. ******* It could be that the charging process is stopping after the CC phase. That would leave you with 65% fuel (second graph). Maybe it takes less time than normal, to fill to 65%. And then less time than normal, to empty it. http://batteryuniversity.com/learn/a..._ion_batteries I can't say much more than that. A battery bought from HP, probably works correctly. Batteries should always be bought from "high volume" sellers. A battery sitting on the shelf in a "mom and pop" computer store, could already be ruined by aging. You want "freshly constructed" laptop batteries for best results. A ten year old battery, may not take a lot of charge cycles due to age. I suspect a disagreement between (2) and (4), and the pack might not be properly designed for G60. The aftermarket suppliers try their best, when making this stuff. They probably weren't trying to save money, by cutting corners. Savvy buyers, use the reviews from previous customers, to get some idea whether the packs are "good". If the supplier is a middle-man and not a manufacturer, then there can be lot-to-lot variation. Like, if the middle-man buys from Larry one day ("good" pack) and from Moe the next day ("bad" pack), then even sellers with reviews may not be enough. If the batteries were nickel cadmium, like many years ago, there wouldn't be all these features. Batteries are this complicated, because of the risk of fire with this particular battery chemistry. Paul Thanks to all for the good info. I will stick to buying only HP batteries and not use the battery at all if I am using the charger. Andy |
#6
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Laptop battery
On Tue, 28 Nov 2017 16:54:50 -0500, Paul wrote:
be in a better condition to detect when it's time to hibernate the computer (before the battery drops below 0%). If the battery loses 0.1% of its life on each full How can a battery go BELOW 0% ??? That dont seem possible.... |
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Laptop battery
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#9
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Laptop battery
On Tue, 28 Nov 2017 18:19:56 -0500, Paul wrote:
There are good battery types out there. But they're not suitable for end-users. https://en.wikipedia.org/wiki/Vanadium_redox_battery Time durability 20-30 years Cycle durability 100,000 cycles Not every battery type is doomed. Just the battery types they sell to consumers. It wouldn't make sense to sell you a battery that would last, now would it. ******* And you know car batteries are a scam, right ? It is possible to make good car batteries. I had a Panasonic sealed battery (no-maintenance) last for seven years. The replacement batteries I get locally, aren't nearly as good. **** car batteries now, last for around two years. Battery construction varies, as to whether a battery is suited to deep discharge or not. The thing about car batteries (the ones with a little calcium added to the plates to "resist vibration"), is they're ruined after only one or two deep discharges. You had better have automatic headlights which switch off on the car, with that battery type. Paul I have an "antique" Allis Chalmers farm tractor from around 1960. When I bought it, I found that the generator (not alternator) was polarized backward. The body of the tractor was intended to be POSITIVE GROUND. However when I connected a battery charger I saw lots of sparks. A multimeter confirmed the polarity was reversed, meaning that the battery itself was charged backward. In other words, the post marked (POS+) was Negative and vice versa. (Yes, this even puzzled several pro mechanics). It turns out that this can and did happen with the old generators if they were not polarized everytime the battery is disconnected. (but it was a rare occurance). While trying to understand this whole mess, I noted the punch out date thingie on the battery. That battery was 15 years old, and it still took a charge. I was stunned..... If they made them half as good as that now-a-days, I'd be happy. Not only was that battery 15 years oold, but it had been abused to the limit by reversing it's polarity. I did replace it though. It was weak, and I was told to NOT try to reverse the polarity another time, since that could completely ruin the battery, damage the charging components, or possibly even make the battery explode. In order to reverse it, it needs to be drained to ZERO volts and remain that way for many hours. (in other words, leave the headlights on for several days). My guess is that this tractor was not being used and the battery was completely dead. Someone used jumper cables and put the NEG jumper to the ground. Thus, the battery began charging backwards and remained that way. By the way, this was a common 12V battery just like those in cars. |
#10
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Laptop battery
wrote:
On Tue, 28 Nov 2017 18:19:56 -0500, Paul wrote: There are good battery types out there. But they're not suitable for end-users. https://en.wikipedia.org/wiki/Vanadium_redox_battery Time durability 20-30 years Cycle durability 100,000 cycles Not every battery type is doomed. Just the battery types they sell to consumers. It wouldn't make sense to sell you a battery that would last, now would it. ******* And you know car batteries are a scam, right ? It is possible to make good car batteries. I had a Panasonic sealed battery (no-maintenance) last for seven years. The replacement batteries I get locally, aren't nearly as good. **** car batteries now, last for around two years. Battery construction varies, as to whether a battery is suited to deep discharge or not. The thing about car batteries (the ones with a little calcium added to the plates to "resist vibration"), is they're ruined after only one or two deep discharges. You had better have automatic headlights which switch off on the car, with that battery type. Paul I have an "antique" Allis Chalmers farm tractor from around 1960. When I bought it, I found that the generator (not alternator) was polarized backward. The body of the tractor was intended to be POSITIVE GROUND. However when I connected a battery charger I saw lots of sparks. A multimeter confirmed the polarity was reversed, meaning that the battery itself was charged backward. In other words, the post marked (POS+) was Negative and vice versa. (Yes, this even puzzled several pro mechanics). It turns out that this can and did happen with the old generators if they were not polarized everytime the battery is disconnected. (but it was a rare occurance). While trying to understand this whole mess, I noted the punch out date thingie on the battery. That battery was 15 years old, and it still took a charge. I was stunned..... If they made them half as good as that now-a-days, I'd be happy. Not only was that battery 15 years oold, but it had been abused to the limit by reversing it's polarity. I did replace it though. It was weak, and I was told to NOT try to reverse the polarity another time, since that could completely ruin the battery, damage the charging components, or possibly even make the battery explode. In order to reverse it, it needs to be drained to ZERO volts and remain that way for many hours. (in other words, leave the headlights on for several days). My guess is that this tractor was not being used and the battery was completely dead. Someone used jumper cables and put the NEG jumper to the ground. Thus, the battery began charging backwards and remained that way. By the way, this was a common 12V battery just like those in cars. There is a "formation" process for lead acid batteries, but I don't know whether it's reversible or not, or even what chemical step it causes. https://www.google.com/patents/US3929505 I thought the idea was, that the electrodes in a lead acid battery weren't the same (weren't perfectly symmetric), so the battery properties won't necessarily be all that good if it's reversed. Or if there was a way to reverse it. As for the tractor, apparently you can get alternator conversion kits for at least some generator based tractors. Generators are horrible devices, in that the output rises with RPMs. There is no closed loop feedback system to tame them. The generator on my bicycle is an example. It produces 6V at 500mA. It's considered to be a "constant current source". It tries to pump the 500mA, no matter what the voltage. If you "overload" the bicycle generator, the voltage drops (maybe it makes 5V at 500mA). On the other hand, if you leave the bicycle generator open circuit, it *still* tries to push the 500mA, but the resistance of the air is too high to allow that. So the generator voltage rises to a voltage proportional to RPM rate. The faster it spins, the higher the voltage. Apparently you can get 50 to 100V off the thing in that condition (open circuit). No, I haven't tested for that :-) But I did take these properties into account when designing a LED headlight for it. The 500mA was selected as a saturation condition during the design of the generator. You select light-bulbs with 12 ohms of resistance (when glowing), and everything works perfect. If you use the wrong bulb, the voltage can shoot up, ruining the bulb. (I lost a very nice sealed beam headlight that way, while riding down a hill.) The tractor generator should be similarly untamed. At low RPMs, it's not going to charge the battery. At high RPMs, a means is needed to tame the output. And I cannot imagine what cack-handed solution they would have used. The automotive industry always finds a "hunk of iron" way to fix stuff like this, so I really don't want to know how that works :-) Nothing in electrical design around engines, is ever pleasant to read about. It always involves abusing stuff, stuff that wears out. The "alternator" on the other hand, is a closed loop feedback system. By adjusting the field winding, the output can be tamed for the engine RPMs at the moment. And the voltage regulator is in control of the field winding. It's still a pretty crude system, as, for example, the voltage regulator might not be temperature compensated, and who knows whether the "charging target voltage" of the voltage regulator, is correct for the atmospheric temperature applied to the battery casing. Battery voltage varies wildly with temp, and the terminal voltage isn't the same at -20C versus +20C. And this is why doing a simple-minded multimeter voltage check on a battery, is meaningless... unless you used a chart to correct for temperature. As otherwise, in the cold, a "full" battery can look "empty", just based on a multimeter reading. Paul |
#11
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Laptop battery
On 11/29/2017 8:55 PM, Paul wrote:
wrote: On Tue, 28 Nov 2017 18:19:56 -0500, Paul wrote: There are good battery types out there. But they're not suitable for end-users. https://en.wikipedia.org/wiki/Vanadium_redox_battery Time durability 20-30 years Cycle durability 100,000 cycles Not every battery type is doomed. Just the battery types they sell to consumers. It wouldn't make sense to sell you a battery that would last, now would it. ******* And you know car batteries are a scam, right ? It is possible to make good car batteries. I had a Panasonic sealed battery (no-maintenance) last for seven years. The replacement batteries I get locally, aren't nearly as good. **** car batteries now, last for around two years. Battery construction varies, as to whether a battery is suited to deep discharge or not. The thing about car batteries (the ones with a little calcium added to the plates to "resist vibration"), is they're ruined after only one or two deep discharges. You had better have automatic headlights which switch off on the car, with that battery type. Paul I have an "antique" Allis Chalmers farm tractor from around 1960. When I bought it, I found that the generator (not alternator) was polarized backward. The body of the tractor was intended to be POSITIVE GROUND. However when I connected a battery charger I saw lots of sparks. A multimeter confirmed the polarity was reversed, meaning that the battery itself was charged backward. In other words, the post marked (POS+) was Negative and vice versa. (Yes, this even puzzled several pro mechanics). It turns out that this can and did happen with the old generators if they were not polarized everytime the battery is disconnected. (but it was a rare occurance). While trying to understand this whole mess, I noted the punch out date thingie on the battery. That battery was 15 years old, and it still took a charge. I was stunned..... If they made them half as good as that now-a-days, I'd be happy. Not only was that battery 15 years oold, but it had been abused to the limit by reversing it's polarity. I did replace it though. It was weak, and I was told to NOT try to reverse the polarity another time, since that could completely ruin the battery, damage the charging components, or possibly even make the battery explode. In order to reverse it, it needs to be drained to ZERO volts and remain that way for many hours. (in other words, leave the headlights on for several days). My guess is that this tractor was not being used and the battery was completely dead. Someone used jumper cables and put the NEG jumper to the ground. Thus, the battery began charging backwards and remained that way. By the way, this was a common 12V battery just like those in cars. There is a "formation" process for lead acid batteries, but I don't know whether it's reversible or not, or even what chemical step it causes. https://www.google.com/patents/US3929505 I thought the idea was, that the electrodes in a lead acid battery weren't the same (weren't perfectly symmetric), so the battery properties won't necessarily be all that good if it's reversed. Or if there was a way to reverse it. As for the tractor, apparently you can get alternator conversion kits for at least some generator based tractors. Generators are horrible devices, in that the output rises with RPMs. There is no closed loop feedback system to tame them. The generator on my bicycle is an example. It produces 6V at 500mA. It's considered to be a "constant current source". It tries to pump the 500mA, no matter what the voltage. If you "overload" the bicycle generator, the voltage drops (maybe it makes 5V at 500mA). On the other hand, if you leave the bicycle generator open circuit, it *still* tries to push the 500mA, but the resistance of the air is too high to allow that. So the generator voltage rises to a voltage proportional to RPM rate. The faster it spins, the higher the voltage. Apparently you can get 50 to 100V off the thing in that condition (open circuit). No, I haven't tested for that :-) But I did take these properties into account when designing a LED headlight for it. The 500mA was selected as a saturation condition during the design of the generator. You select light-bulbs with 12 ohms of resistance (when glowing), and everything works perfect. If you use the wrong bulb, the voltage can shoot up, ruining the bulb. (I lost a very nice sealed beam headlight that way, while riding down a hill.) The tractor generator should be similarly untamed. At low RPMs, it's not going to charge the battery. At high RPMs, a means is needed to tame the output. And I cannot imagine what cack-handed solution they would have used. The automotive industry always finds a "hunk of iron" way to fix stuff like this, so I really don't want to know how that works :-) Nothing in electrical design around engines, is ever pleasant to read about. It always involves abusing stuff, stuff that wears out. The "alternator" on the other hand, is a closed loop feedback system. By adjusting the field winding, the output can be tamed for the engine RPMs at the moment. And the voltage regulator is in control of the field winding. It's still a pretty crude system, as, for example, the voltage regulator might not be temperature compensated, and who knows whether the "charging target voltage" of the voltage regulator, is correct for the atmospheric temperature applied to the battery casing. Battery voltage varies wildly with temp, and the terminal voltage isn't the same at -20C versus +20C. And this is why doing a simple-minded multimeter voltage check on a battery, is meaningless... unless you used a chart to correct for temperature. As otherwise, in the cold, a "full" battery can look "empty", just based on a multimeter reading. Paul Car generators have had regulators for as long as I can remember. 1955 was the oldest car I've had. Was sloppy. Just a relay that had a soft spring that gave a couple of levels of control. |
#12
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Laptop battery
mike wrote:
Car generators have had regulators for as long as I can remember. 1955 was the oldest car I've had. Was sloppy. Just a relay that had a soft spring that gave a couple of levels of control. So I take it then, it was just designed to destroy the battery ? :-) That sounds like the car companies I know and love. Does it ever stop charging the battery, or does the '55 battery get ruined ? There are two ways to ruin a battery - sulfation (too little charging between uses) and corrosion (too much charging). https://en.wikipedia.org/wiki/Lead%E..._desulfatio n I had the exact opposite problem here with my car, where the alternator and voltage regulator were hardly pumping any current into the battery. And I couldn't really tell if the net charging rate was sufficient to keep the car starting or not. I kept having to throw the charger on it in the winter. And the headlights behaved normally, not like headlights behave on older cars (dim at low RPM). It was almost like the voltage regulator wasn't regulating to the correct voltage. Every time I work on cars and their charging systems, none of my measurements make any sense :-) The car battery voltage is never even remotely close to textbook, and I end up not really knowing what's going on. I have a hydrometer, and that's the only sanity check that really works. https://en.wikipedia.org/wiki/Hydrometer Battery hydrometer ... Tables are used to correct the reading to the standard temperature Paul |
#13
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Laptop battery
On Thu, 30 Nov 2017 02:33:58 -0500, Paul wrote:
mike wrote: Car generators have had regulators for as long as I can remember. 1955 was the oldest car I've had. Was sloppy. Just a relay that had a soft spring that gave a couple of levels of control. So I take it then, it was just designed to destroy the battery ? :-) That sounds like the car companies I know and love. Does it ever stop charging the battery, or does the '55 battery get ruined ? There are two ways to ruin a battery - sulfation (too little charging between uses) and corrosion (too much charging). That generator obviously did not ruin my tractor battery which lasted 15 years. THe generator has a voltage regulator, There are 4 wires going to it, there are 3 relays inside and some other parts. I dont know exactly how it works, but it does work. However those generator voltage regs do seem to need a lot of care, and/or replacements. My Allis model is one of the few tractors which are very difficult to change to an alternator. Changing the wiring is easy, but not mounting the alternator, which needs to line up with the fan pulley. The engine mount and bracket are in the way, and they cant be modified, so it's very hard to mount the alternator, other than cutting away part of the hood and having it sticking way outside the tractor. Otherwise I'd have an alternator in there. My old International Farmall tractors, which I've owned 3 of, are easy to convert. I have also converted a Case tractor and a few more Farmall's owned by friends. https://en.wikipedia.org/wiki/Lead%E..._desulfatio n I had the exact opposite problem here with my car, where the alternator and voltage regulator were hardly pumping any current into the battery. And I couldn't really tell if the net charging rate was sufficient to keep the car starting or not. I kept having to throw the charger on it in the winter. And the headlights behaved normally, not like headlights behave on older cars (dim at low RPM). It was almost like the voltage regulator wasn't regulating to the correct voltage. Dont matter if it's a generator or an alternator. If the voltage regulator is not working properly, it wont charge properly. However, the V.R.s on alternators are simpler, and most are now soild state. No one has made a solid state V.R. for generators (that I know of). Every time I work on cars and their charging systems, none of my measurements make any sense :-) The car battery voltage is never even remotely close to textbook, and I end up not really knowing what's going on. I have a hydrometer, and that's the only sanity check that really works. https://en.wikipedia.org/wiki/Hydrometer Battery hydrometer A hydrometer is a good tool, so is a battery tester. But a battery tester is not just a multimeter, it has a large resistor that loads the battery. A battery must be under load to test it properly. (even the small D C AA or AAA batteries need a tester that loads it. ... Tables are used to correct the reading to the standard temperature Paul |
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Laptop battery
On 11/29/2017 11:33 PM, Paul wrote:
mike wrote: Car generators have had regulators for as long as I can remember. 1955 was the oldest car I've had. Was sloppy. Just a relay that had a soft spring that gave a couple of levels of control. So I take it then, it was just designed to destroy the battery ? :-) That sounds like the car companies I know and love. Does it ever stop charging the battery, or does the '55 battery get ruined ? There are two ways to ruin a battery - sulfation (too little charging between uses) and corrosion (too much charging). Was the best affordable technology available. Not having an alternative is a strong motivator to accept what you get. |
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