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Q Can I mix and match lithium and lead acid batteries?
Do you have an opinion on the LE300 28Ah batteries produced by BOS AG, which I read about in a boating magazine recently? Details are on its website smart-battery-system.com/en but apparently they are intended to be simply connected in parallel to a lead acid battery, stringing together as many units as you wish to make up the desired capacity.
The battery management system (BMS) then arranges for the lithium units to do most of the work with the lead battery being used as a reserve. There appears to be no need for any change in the wiring or charging system. If it really is that simple, they would seem to be an ideal way to upgrade leisure battery capacity. According to the website, the Hymer Group uses them.
Robert Davis
A Hymer floated the mixed battery idea some years back in 2018 and, yes, it used the LE300 arrangement from BOS AG. Hymer today offers a mixed arrangement with various mixes of lead acid and lithium.
The thinking here is that the lithium batteries do not need a high-current BMS because high-current peaks are supplied from lead acid batteries. Then, over time, these are topped up from the lithium cells. I do not believe it is as simple as connecting lead acid and lithium directly in parallel, but rather via a specialist battery management system.
The LE300 data sheet says, “The charging characteristic of the EBL is preset to AGM 14.7V. The lead acid battery gets higher priority loaded. From approx 80% charge level, the HY-Tec lithium battery 135 is charged in parallel, with the excess energy that the lead battery can no longer absorb. The lead acid battery is still supplied with enough power to fully charge it. The charging current is limited to 12.5A per LE300 module. Th at means the HY-Tec lithium battery 135 can be charged with up to 75A.” This is why I suspect it uses a specialist BMS.
Personally, I have removed three 95Ah AGM batteries and replaced them with just a single 150Ah lithium battery with a 150A BMS, which saves 63kg of weight.
Clive Mott
Q Where can I source a Spanish gas regulator?
I have a full 13kg Cepsa Spanish gas bottle. Do you know of anywhere in UK I can get a regulator to fit this bottle? I’ve tried all the local dealers in my area without success.
A Wilson
A Gaslow has a good range of Spanish adaptors, some of which are regulators and some a connection to then connect to a W20 pigtail, which then allows fitment to a bulkhead regulator. If you end up looking at an adaptor, pigtail and bulkhead regulator, then the cost of this will exceed the value of the gas you have.
Alternatively, again from Gaslow, you can source an adaptor (01-1671) for £16.50 and a simple low-pressure bottle top regulator (01-4337) for £8.50, plus delivery. ☎ 01509 377377 gaslowdirect.com
Clive Mott
